# Eurovan: adding a transmission temperature gauge



## KBATTPO (Jan 15, 2001)

*2003 Eurovan: adding a transmission temperature gauge*

I have finally gotten around to putting together this long overdue write-up on the subject. Hopefully it will answer some questions that have been popping up on the board lately.

I am old school and as such do believe that there is never enough gauges or useful information in a car. Especially when it comes to such mission critical and potentially expensive to replace item as the automatic transmission in our vans.

I chose Taiwanese made Rico PAC45OTC oil temperature gauge because it was smaller than most (45mm OD) and its dial was a near perfect match for the Eurovan's OEM gauges. 










The only thing that did not match was the white peripheral dial illumination (the red needle illumination in the center was spot on). The hopeless
perfectionist in me could not leave well enough alone so I ordered a few blue SMD LEDs from Digi-Key (492-1272-1-ND; 2.80mm L x 1.20mm W; Surface Mount, Right Angle; 450mcd brightness; 120° viewing angle; 471nm wavelength).

In order to replace the LEDs I had to completely disassemble the gauge. And prior to removing the pointer I had to take down its characteristics (sensor resistance vs. actual temperature). So, before starting the brain trepanation I boiled the sender in a pot on the stove, with a thermometer in the water and a
multimeter across the sender's terminals. BTW, this simple test had revealed that Rico did not do a very good job at calibrating their gauge. The graph
representing the temperature indicated by the gauge was quite a bit off at 40°C actual and eventually intersected with the graph from the sender at about 90°C actual. No big deal, I will correct it at the time of reassembly.










So I secured the gauge in the Panavise and took it completely apart:










Here are the LEDs. The red ones illuminate the pointer (marked with red arrows) and stay put. The white ones light up the dial periphery (marked with blue arrows)










and are getting replaced with the blue LEDs sourced from Digi-Key:










Testing the blue illumination after the LED replacement:



















Now is a good time to calibrate the gauge per our chart above. The potentiometer in the back is being used to simulate the actual temperature sender. I
didn't feel like doing this on the kitchen table boiling the actual sender in a pot of water once again hence the need for the sender emulator.










... to be continued.


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## KBATTPO (Jan 15, 2001)

Next we need to install the temperature sender into the transmission. I found that the M10x1 port for the service plug (denoted as item #12 in the ETKA illustration below) is a perfect place for it:










However prior to installing the sender we need to overcome one little inconvenience. The sender supplied with the gauge had the male tapered English 1/8 NPT thread whereas the threaded bore in the transmission case had the female straight Metric M10x1 thread.

Since an 1/8" NPT to M10x1 adapter was not going to fit in that location I had to come up with a better solution. 1/8" NPT thread measures about ~9.5mm on the narrow end and ~10.5mm on the wide end so it is very close to 10mm. Its pitch is 27 tpi and given that 1"=25.4mm its Metric equivalent is 0.94mm which is very close to the 1mm pitch of the M10x1 thread. So I secured the sender in the vise and ran a M10x1 die over its threaded part. The pitch error was so minuscule that I could not see a single damaged crest on the whole length of the threaded part. I've been successfully using this hack in various Audis ever since back in 1992 I retrofitted an Autometer oil pressure gauge in an old 1985 Audi 5000.

After that I added a 10mm Cu washer to the sender, some Teflon tape to its thread and screwed the sender directly into the transmission case. In the picture below it's the brass thing with the Si boot for the high tension fly-back transformer wire out of an old CRT TV on top of it with the single blue wire coming out of it:










I ran that single blue wire up from the engine compartment through the grommet in the firewall into the dashboard:










... to be continued.


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## jjvincent (Dec 8, 2003)

Good work!

That's the trans pressure port. You could even do a trans temp and trans pressure reading from there.

If you are looking for oddball adapters, this place usually has them because if you ever worked on an English formula car, it's a mix of about every type of fitting and fastener you can imagine. The best are the M8 to 3/8-16 adapter studs to mate a VW transaxle to a Hewland gearbox on an old Ralt Super Vee. Tie rods that have a Metric Heim Joint on one end and British Whitworth on the other.

https://www.pegasusautoracing.com/


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## marshy (Aug 7, 2012)

This is some great work. Thanks! :beer::thumbup::beer:
I can't help but ask why you chose Celsius units for the gauge. Is your engine coolant gauge also Celsius?


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## KBATTPO (Jan 15, 2001)

> I can't help but ask why you chose Celsius units for the gauge. Is your engine coolant gauge also Celsius?


Because I was born and raised in the logical elegance of the metric system. I had encountered the not used anywhere else in the world Fahrenheit scale for the first time only when I had moved to the States at the tender age of 29. The proverb about an old dog and new tricks comes to mind.  Luckily being a Physicist I only have to deal with non-Metric units during grocery shopping.

The engine coolant gauges in 2 out of the 3 cars in my household are in Celsius. The Eurovan will get one as soon as I come across a cheap broken instrument cluster from a Canadian or European VW to act as a donor.


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## KBATTPO (Jan 15, 2001)

jjvincent said:


> If you are looking for oddball adapters, this place usually has them because if you ever worked on an English formula car, it's a mix of about every type of fitting and fastener you can imagine. The best are the M8 to 3/8-16 adapter studs to mate a VW transaxle to a Hewland gearbox on an old Ralt Super Vee. Tie rods that have a Metric Heim Joint on one end and British Whitworth on the other.


Yeah, brings back the not-so-sweet memories of my brief affair with a (gasp) TransAm in the early 1990s and its nightmarish Metric and English mix of fastener assortment as if its designers in Detroit were reaching for the fasteners' bins at random w/o even looking. I remember promising to self to never ever buy an American car again simply because I did not want to deal with the mind wrecking archaic fractional nonsense ever again.


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## jjvincent (Dec 8, 2003)

The units thing is pretty funny. In the end, everyone uses metric for everything but there are a few things that people will just continue to use in the English system. It's funny that certain things (i.e. plumbing, hvac/r) are not in metric. At least we don't measure distance in Parsec's.

In racing, we are always scaling and aligning cars. When I do toe, it's in mm instead of inches. Main reason is because it's a royal PIA to set up and do the toe in inches. I even run H&R springs that are in metric. So, people are really confused when it comes to spring rates (unless they are from Europe).


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## KBATTPO (Jan 15, 2001)

I hear you. In the late 1990s I built a jig out of a few lasers, gravity sensors and Metric Ikea paper measuring strips laminated to Aluminium angles and been aligning my cars at home ever since. Can't imagine doing this in simple fractions in the English system. 

Slowly but surely the US is moving towards the Metric system. In my field back 20 years ago all IC dies were scaled to the 0.100" pin pitch. About 10 years ago places like Digi-Key had begun listing components in the Metric system as well albeit the pitch still remained Imperial (2.54mm). Nowadays pretty much everything is Metric thanks to China squarely cornering the electronics industry. I still see an inch sized pitch here and there but those components were probably made off some old dies and are being slowly phased out.

I guess the recent multi-billion dollar Mars probe catastrophe has restarted the metrification process.


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## Dominicdrl (Jun 2, 2010)

When I installed an analog gauge to monitor transmission temps, I used an Auto-Meter gauge, with their optional blue LED that almost perfectly matches the stock gauges. 
The sender was installed via a hole drilled in the transmission fluid pan while I was doing a fluid change. This way the gauge is taking the reading from the same area as the temperature sensor built into the transmission diagnostics.


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## KBATTPO (Jan 15, 2001)

Would be interesting to see pictures of this setup. The more various options we have in this topic the better.


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## KBATTPO (Jan 15, 2001)

Now we need to install the gauge into the dashboard. The spot wasted by the triangular 4-way flasher switch is the obvious choice but first we need to relocate this switch. 

A 1999-2005 Passat 4-way flasher switch 3B0-953-235-D fits one of the blanks in the Eurovan dashboard perfectly, has the same exact style and is plug and play. Once the emergency flasher switch is out of the way we can install the gauge.

The hole for the gauge is cut with a suitable hole saw - I did not make a note of its size at the time but you can mike up your actual gauge and go from there. Scotch up the whole panel to a suitable piece of plywood so that the the center pilot drill bit will have something to drill into inside the triangular cutout in the dashboard panel. Don't try to drill that large hole without this helper piece of plywood! Your hole saw will walk and mess up the dashboard panel. Regretfully I did not take pictures at the time of drilling mine so I can't show you exactly what I did.

Here is the gauge already installed into the dashboard panel. Below you can see the Passat 4-way flasher switch installed into the main block of switches.










A day shot:










and a night shot.










Below are some pix of the transmission temperature gauge in action.

A copy and paste from my earlier post in another thread: 
Today was a nice and warm day here in Philly (gotta love +17°C in mid-December!). As you can see in the pic below the transmission temperature hovered just above +60°C. Sorry for the lousy picture quality - I seldom use my cellphone for picture taking and today was that rare occasion.










Some pix taken the next day in daylight. As you can see from the Climate Control display the ambient temperature that day was +14°C and the gauge was hovering at about +45°C while I was driving.










After I arrived home I just stood there for a while with the engine running fiddling with the laptop case and such. Within minutes (3 minutes actually: 15:44 on the clock in the first picture vs. 15:47 in the second one) in the absence of the airflow through the auxiliary transmission fluid cooler the transmission fluid temperature had begun creeping up due to heat soak. You can see it is already @ +50°C at the same ambient temperature of +14°C.
This illustrates the effectiveness of the aftermarket transmission cooler for the Eurovan quite well.










What would I do differently if I were to start over again?

In the hindsight I should've chosen a slightly different colour of the LEDs that I had used for dial illumination. Turned out the original dashboard illumination in the Eurovan had a bit of a violet hue to it whereas the dial of the transmission temperature gauge illumination is closer to pure blue. Of course this discrepancy had only become evident after I installed the gauge into the dashboard and could compare their illumination side by side.

The specs of the LEDs that I had used listed 471nm for the dominant wavelength. Digi-Key also sells blue LEDs with a shorter wavelength (460-465nm) which should give out the light shifted a bit into the violet part of the spectrum. If I ever decide to do this again I'll be sure to try those LEDs but for the time being the existing LEDs will have to do.


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## marshy (Aug 7, 2012)

Great location! Nice info on the passat 4-way switch!
I suppose if one wasn't too confident with a hole saw they could mark the hole and carefully cut it with a dremel tool.

If you're not pedantic, and fancy freedom units :laugh:, this new south performance gauge from ECS can be had with the correct indigo color, and at 2 3/64", it's only 9/32" larger than the Rico gauge. :laugh:


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## KBATTPO (Jan 15, 2001)

http://www.zmescience.com/other/map-of-countries-officially-not-using-the-metric-system/


They forgot to mention 12 hours in a day, week starting on Sunday (while somehow still calling Saturday and Sunday "the weekend") arbitrary reciprocal "gauges" for thickness of materials and a million other equally awesome "freedom units" not used anywhere in the world except the USA, Liberia and Burma.

The gauge is good indeed. However @ 52mm OD it might be problematic to fit in that particular spot. The 45mm gauge occupied pretty much all of the available RE.


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## marshy (Aug 7, 2012)

Metaphorically, the eurovan is like the imperial system of the van world. It's outdated, confusing, and for some, totally illogical. But t's great for those who know and love it. 
If I wanted to be like everyone else, I would have bought a Sienna or Odyssey.:laugh:


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## KBATTPO (Jan 15, 2001)

Religious beliefs aside, the Sienna is a better van in almost every aspect. No opinion on the Odyssey - never drove one.
None the less we chose to buy the Eurovan for its several distinct advantages over the Sienna.

The English system of measurement however has no advantages over the Metric system. Its continued use in the US can be attributed to reasons not based on merits and is rooted in the inertia of the general population and in the staggering monetary investment in the existing infrastructure, tooling etc. The trouble is the longer we procrastinate the more heavily this inevitable transition is going to burden the forthcoming generations. Such a transition should be forced upon by the government like it was mandated in Europe. It's one of those occasions when "freedom" should be sidelined in the name of the obvious common good and the long term national benefit.


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## kafercup (Sep 17, 2000)

I love the gauge install, i'll have to do that this spring. As to your double-din head unit install, did you source a euro double din dash support bar or cut the original US one?


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## KBATTPO (Jan 15, 2001)

After after finding out how ridiculously expensive the European dashboard brace was I decided to modify the existing one. It's not that big a deal, really. I am planning to write a separate post on the double DIN multimedia unit installation as soon as I find some time to do so.


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## Kwabena (Mar 29, 2002)

Wow, just wow sir!


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## KBATTPO (Jan 15, 2001)

Since I can't leave well enough alone I took the gauge apart once again and replaced the blue SMD LEDs 492-1272-1-ND, 471nm from Digi-Key with the 604-APA3010QBC/G-GX, 465nm LEDs from Mouser. As the shorter wavelength implies their colour is shifted a bit more towards the violet part of the spectrum. They are indeed a bit closer to the original VW illumination:










Since I had to pull the needle and the dial off the gauge I had to recalibrate it again. VAG-COM thinks that the temperature reading after calibration is spot on:


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## Itsamoto (May 1, 2014)

Kbattpo -- this is awesome. :thumbup:

Somehow I missed this thread when it started -- but its such a useful mod in tandem with the hazard switch mod. :thumbup:

I will add a shot in the arm here for the imperial system. While I am a Canadian and raised with the metric system, we are very much tied to US standards and so everybody here uses both systems. What I love about imperial, or Base-12 systems -- is that its a far more practical system for real world applications (where you can divide evenly into halves, thirds and quarters) -- which is much better than Base-10 metric. There is a good reason why at the grocery store you get a dozen eggs and not 10.


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## KBATTPO (Jan 15, 2001)

How interesting:










http://www.vwt4forum.co.uk/showthread.php?t=368183

No, I did not get my idea from that guy.


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## Itsamoto (May 1, 2014)

KBATTPO said:


> http://www.vwt4forum.co.uk/showthread.php?t=368183


I found some amusing highlights in that thread include a "Eurovan" badge and US-Spec amber turn signal housings. :laugh:

_The grass is always greener on the other side._.


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## KBATTPO (Jan 15, 2001)

Itsamoto said:


> ... US-Spec amber turn signal housings. :laugh:
> 
> _The grass is always greener on the other side._.


True, that. Hopefully he was strictly after that antique 1980s look and did not combine the front orange blinkers with the front orange directional lights the US style. Probably not since this is illegal under the European lighting code.


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## gti_matt (Oct 9, 1999)

KBATTPO said:


> True, that. Hopefully he was strictly after that antique 1980s look and did not combine the front orange blinkers with the front orange directional lights the US style. Probably not since this is illegal under the European lighting code.


EU-spec T4s have the white parking lamps in the headlamps instead. However, the US housings for the corner lamps have no raised bump that act as the side-visible turn signal, so these lamp housings probably would be illegal anyway for not meeting that.


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## KBATTPO (Jan 15, 2001)

I was wondering why there were no mandatory fender mounted blinkers on European T4. Turns out they are built into the corner blinkers. Would still prefer to have them on the fenders because they would be more visible when looking from the flank. Then again, perhaps I am simply used to having them on the fenders.


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## gti_matt (Oct 9, 1999)

KBATTPO said:


> I was wondering why there were no mandatory fender mounted blinkers on European T4. Turns out they are built into the corner blinkers. Would still prefer to have them on the fenders because they would be more visible when looking from the flank. Then again, perhaps I am simply used to having them on the fenders.


Agreed. When I had my '00 T4 and installed E-code clear assemblies with the side "bump" in them, the light wasn't all that visible, especially in the daytime.

Interestingly, when I was in Israel in 2010, the few T4s I saw there (not very popular vehicle there) actually did have extra side indicators on the front fenders. This suggests to me that something about Israel's vehicle code perhaps wasn't adequately met by the built-in bump on the corner lamp.

Here's an example:


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## Evripos (Nov 10, 2004)

KBATTPO may I ask where you purchased the Rico PAC45OTC temp gauge?


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## KBATTPO (Jan 15, 2001)

Here you go, Evripos. I bought from these folks:
RICO 45mm Clear Lens White Led Oil Temp Meter Gauge

Say, it's not your silver Eurovan parked in front of the Doylestown Y once in a while by any chance?


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## Evripos (Nov 10, 2004)

Thank you for the info.
I'm afraid that Eurovan is not mine. I have been storing it for the last three years. I think I'm ready this year to swap out my auto transmission with a 5-speed manual one.


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## KBATTPO (Jan 15, 2001)

Glad I could help.

Where are you in Philly? I'd love to see the manual transmission swap. Who's going to do the job? Self? Shop?


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## Evripos (Nov 10, 2004)

I always work on my cars.


Send me a private message when you have a chance for the more personal info.


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## ovsa (Jan 30, 2009)

*Transmission port location*

hi ,

thanks for the informative post.

I was looking around for a port to install the temp sensor on my 1996 EVC, which i believe is a 01P transmission but could seem to locate anything.

Can you give me a general idea of where to find it, and do i need to remove anything that is currently in that port?

thanks


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## KBATTPO (Jan 15, 2001)

http://forums.vwvortex.com/showthre...ture-gauge&p=91296402&viewfull=1#post91296402


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## jjvincent (Dec 8, 2003)

I'm wondering. What is too high for a transmission temp? What happens if it goes too high? What do you do if it goes too high? If you are going to put a gauge on it, you should have some sort of number where it becomes a problem. It's like in racing, we program in warnings for the dash when a temp is too high or a pressure is too low. If I don't know those numbers, then I have no idea what to do. For example, a max water temp on an LS6 for water temp is around 260 F but on a BMW M54B30, it's 230 F. Each engine gets a different warning that I set up.

With people installing temp gauges, it might be a good idea to just have a number just so you know when there's something going wrong.


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## ovsa (Jan 30, 2009)

*Transmission temperatures.*

Finally took the 96 EVC for a long weekend camping trip in the B.C. Rockies.

First trip i've taken since i bought it and it some modifications to it. One of them being a AFT cooler and temp. gauge.

In retrospect i should have installed the gauge first and ran it around with the stock ATF cooler to see what kind of temperatures i was running. Then i would be able to see if the aftermarket cooler was an improvement or just a waste of cash. Most people say they work good so i'll go with that.

Anyway i wanted to post some readings to see if its similar to other people.

It has been a hot week here , around 80- 85 deg. f. In stop n go city traffic my gauge was running at about 200-210 ( seems pretty high) Got out to the highway and it ran steady at 170-180 deg.. Some of the long uphill summits brought me back up to 210 deg. Nice flat evening driving got me down as low as 150.

I was surprised at the range it went through and the effect of the ambient air temp. Yesterday was 87 deg and it ran a bit higher at 180-190. 

This is the five cylinder-2.5 liter so it has to work pretty hard climbing those hills. 

i also noticed it is kinda slow to downshift, but i guess that is for another day.

Should mention the engine ran nice and cool most of the time , about 1/3 way up the gauge ( no temp. markings on that one).

thanks for any input.


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## KBATTPO (Jan 15, 2001)

You are at about +100°C which seems rather high. AT fluid starts to break down above +90°C. Did you have the bypass valve installed? If yes you might want to remove it altogether and see what happens. It restricts the flow.

Mine never climbs above +80°C in the stop and go traffic here in SE PA regardless of the ambient temperature and it hovers around +60°C ... +70°C while driving. The transmission shifts quickly both up and down.


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## ovsa (Jan 30, 2009)

thanks, if figured that 210 F would be kinda high. 

I never installed a bypass because i will not be using it in the winter. Strictly RV purposes.

I may have forgot to mention that it is a full camper model so somewhat heavier that a regular Eurovan.

So i'm thinking either the cooler is under sized or my placement isn't the best and not getting enough air flow.

I used the TRU cool Mini-Max: Size 4 x 23 x 3/4 inch, 8 plates, 24,000 GVW / 22,000 BTU ratings.

this is what GOWesty sells. I 

if i can figure out how to paste a photo you can see my install or you can see my posts at http://www.thesamba.com/vw/forum/viewtopic.php?t=652075.

thanks again


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## KBATTPO (Jan 15, 2001)

Here's the reading after a run in today's heat:





























Not bad for +37°C ambient here in Philly today with both air conditioners running. Very happy with this auxiliary transmission cooler.


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## LCaufill (Jun 29, 2016)

*Great Tutorial for adding the tranny temp sensor and guage. I'm doing this. Do you have a similarly detailed post for the sound system/gps upgrade shown*

Great Tutorial for adding the tranny temp sensor and guage. I'm doing this to my 2001 EVM now. 
Do you have a similarly detailed post for the sound system/gps upgrade shown in your pics? That's my next upgrade. 
Thx. 
— Lisa


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## Itsamoto (May 1, 2014)

I'm giving up reading temps off the scan gauge (TFT readings are buggy). I'm going to do the trans temp gauge install and found a vw-indigo style gauge/kit that includes a metric thread temp sender made by NewSouth Performance. A bit spendy but it looks like it will do the job - and it includes some kit components. I'm just wondering if the 10mm probe length is going to be okay at the service port?

Indigo temp gauge


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## markcm (Jun 19, 2009)

KBATTPO- fantastic write up, thank you for the contribution.

It looks like you started with a Kenwood and switched to an Android head unit. Can you elaborate on that change? I had a double DIN android for awhile and although it was "neat", I switched to Pioneer for audio quality and consistency. Also, have you tried any OBD app on that headunit such as Torque? With an app, you can display whatever parameters you want from the BUS. That was my favorite part about the android head unit was Torque, its a great app. I also use Dash Command on my iOS devices.


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## KBATTPO (Jan 15, 2001)

Itsamoto, 

yes, the service port will accommodate the 10mm long business end with room to spare. Not sure about the 52mm gauge itself. The 45mm one that I installed was a tight fit and even required trimming the plastic ridges molded to hold the 4-way flasher. I am afraid the 52mm gauge will require a bit more Dremel surgery.


markcm,

I will try to answer this question in a separate topic.


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## Itsamoto (May 1, 2014)

Thanks KBATTPO -- I wasn't sure if the probe was too short to get the temp reading properly.


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## KBATTPO (Jan 15, 2001)

The probe bathes in transmission fluid so I don't think it's length is important so long it does not interfere with the transmission innards.


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## Itsamoto (May 1, 2014)

It fits! There are some ridges on the back of the panel -- that are basically 52mm apart and that was perfect guide to centre the hole. I did however have to cut up the support bracket (behind the panel to get this in). Colour temperature is actually better in person (vs the picture).


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## Fkahlert (Jan 27, 2005)

that looks nice.... I'd be curious about the difference in temperature measurement btwn what you see with the Scanguage and what you see from the probe. My theory is that 1) you will see a more constant measure with the probe (the TFT tends to react very quickly to minor changes in driving) and 2) you may see slightly lower temps than the TFT measure based on where the temp is taken. But again those would be my assumptions. If you now have both, could you provide some insight?
Thanks,
Florian
03 MVWK


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## KBATTPO (Jan 15, 2001)

Itsamoto, thumbs up! I like yours even better than mine. 
Less work too, considering that you didn't have to take the gauge apart to replace the LEDs.


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## Itsamoto (May 1, 2014)

I tried to find the same gauge as KBATTPO - but a local store had this in stock and so it was double convenient not to wait or have to modify it.

But it's not all roses so far, the kit doesn't include a crush washer -- so I leaked some trans fluid on my initial testing. I should know better.  And the wire taps provided look to be for 18 gauge wire, where as in the EV the power and ground wires are something like 14-15 gauge (1.5mm) -- so some new wire taps were needed. It might look good - but its not 100% reliable yet as I have some issues. 

I did test the scan gauge against this direct gauge while just idling and warming up the van. At low temp everything seems good -- I will check again on a highway run. The problem I have with the scangauge is mine has been buggy - the readings get pinned or don't feed back at all at times. Funny though, with the new gauge installed, the scan gauge pulled up its socks and worked (maybe it knows it about to get replaced). 











But most importantly, I think I have to revisit the wiring. I tapped into the cigarette lighter wiring -- but noticed that illuminating the gauge adds 10F to the gauge reading. Lights off and the gauge drops 10F. Bad ground, or bad supply? The gauge never sweeps on start up either - but lights up and reads correctly (+/- 10F) next to the scangauge. 

Lights off:









Lights on: +10F!!!


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## KBATTPO (Jan 15, 2001)

Itsamoto,



What is "wire taps"?
Digital gauges suck. Remember the 1980s obsession with digital watches? The 1990s obsession with digital speedometers? Where are they now?
Pull the gauge out of the dashboard. Measure the resistance of the temperature sender. Leave the sender inside the transmission - it's irrelevant. Replicate the circuit (it's only 3 wires) on the bench, emulating the sender with a suitable resistor. Power the gauge from a 12v lab power supply. It will show some value depending on the resistor that you used. Now connect the illumination wire to the power supply so that the gauge lights up. Did the reading change?


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## Itsamoto (May 1, 2014)

Thanks KBATTPO -- I will try this.

BTW -- I am so glad you own a Eurovan too. :beer:


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## KBATTPO (Jan 15, 2001)

Glad I can help, Itsamoto. 

Actually, one of these days I plan to get even with you by asking you to show me that successfully completed manual transmission conversion of yours even if I'll have to drive for 10 hours to Toronto for that .

And please, do not ever use wire taps, wire nuts, butt connectors, crimp terminals, electrical tape or any other garbage that shadetree mechanics like to use. There is only one acceptable way to deal with wiring, especially in the high vibration, wide temperature range automotive application: flux + solder + heat shrink tubing. This is a double-E speaking. I have dealt with more sloppy circuits and spaghetti wiring that I care to remember. Some of which was burnt to charcoal and to gobs of molten copper and vinyl. The short term time saving by not using a soldering iron is illusory; the long term saving is actually negative because in the end you (or somebody else dealing with this mess after you) will be paying for it several times over with time, money and collateral damage to other components.


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## Itsamoto (May 1, 2014)

KBATTPO said:


> Glad I can help, Itsamoto.
> 
> Actually, one of these days I plan to get even with you by asking you to show me that successfully completed manual transmission conversion of yours even if I'll have to drive for 10 hours to Toronto for that .


I would drive to Toronto to see it get completed too. 

Go see Jack's (B5.5's) -- he's in NJ.


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## KBATTPO (Jan 15, 2001)

So you are not in Toronto (vicinity). Assumption is the mother of all screw-ups  I hope you are not in Vancouver either - it's just too far. I was hoping to pry your brain for the custom transmission adapter.


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## markcm (Jun 19, 2009)

KBATTPO said:


> Glad I can help, Itsamoto.
> 
> And please, do not ever use wire taps, wire nuts, butt connectors, crimp terminals, electrical tape or any other garbage that shadetree mechanics like to use. There is only one acceptable way to deal with wiring, especially in the high vibration, wide temperature range automotive application: flux + solder + heat shrink tubing. This is a double-E speaking. I have dealt with more sloppy circuits and spaghetti wiring that I care to remember. Some of which was burnt to charcoal and to gobs of molten copper and vinyl. The short term time saving by not using a soldering iron is illusory; the long term saving is actually negative because in the end you (or somebody else dealing with this mess after you) will be paying for it several times over with time, money and collateral damage to other components.


Many professionals would disagree, a proper crimp connection is more reliable than solder connection. Granted, either can be done poorly or incorrectly although when done correctly...crimp.


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## KBATTPO (Jan 15, 2001)

Professionals would disagree only because crimping is much quicker and easier; for them time=money with quality being a distant second. 

If time/cost is not an issue as is the case with home repairs then soldering is preferred since it is more reliable long term than crimping. There is no air gap for the moisture to creep in, and there are no dissimilar metals to touch that can create a galvanic couple ready to start a corrosion/oxidation/electrolysis process in the presence of moisture in the air.

This is the reason why high end HiFi shops explicitly forbid their installation technicians from using anything but soldering irons to connect wires together.

I am yet to see a single failed soldered connection regardless of its age whereas I see badly oxidised crimped connections all the time with many of them starting to fail at a certain age almost inevitably. 

And the only reason why OEMs use crimping and not soldering is because crimping is several orders of magnitude quicker than soldering making it suitable for automated assembly lines. Soldering can not be automated except for wave soldering of PCBs. In mission critical applications where even minuscule transient resistances can create unacceptable voltage drops (such as in battery packs for example or in high current applications) soldering is often substituted by spot welding. Spot welding, while more complicated than crimping, can still be automated; while soldering cannot.


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## markcm (Jun 19, 2009)

KBATTPO said:


> Professionals would disagree only because crimping is much quicker and easier; for them time=money with quality being a distant second.
> 
> If time/cost is not an issue as is the case with home repairs then soldering is preferred since it is more reliable long term than crimping. There is no air gap for the moisture to creep in, and there are no dissimilar metals to touch that can create a galvanic couple ready to start a corrosion/oxidation/electrolysis process in the presence of moisture in the air.
> 
> ...


It seems you assume all professionals do it half-baked? Again, I disagree with your claim on soldering vs crimped. 

In the automotive OEM R&D sector (not a production line as you assumed), we crimp for quality and our job includes testing connections in corrosive high vibration environments. We are composed of many "EE's" and many of our staff come from a military background testing aircraft and defense systems. Maybe soldering works well for home stereo but we typically crimp rather than solder because it is more durable in an automotive application. This might mean using a sealed connector but none the less, the terminals are crimped rather than soldered.

Either way, a properly done connection (solder or crimp) with strain-relief vs. a poorly done connection is really what it boils down to. Crimps are not inferior, need not be avoided at all cost, they simply need to be installed correctly; just as when solder is used, it should be applied properly.

Now if we are discussing those scotch-lock splicing "piggyback" connectors, the kind that you press on to an existing wire and it "bites" into it so you can tap in a secondary wire; I will totally agree with you. Those connectors do not perform well and are prone to failure.


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## jjvincent (Dec 8, 2003)

> Either way, a properly done connection (solder or crimp) with strain-relief vs. a poorly done connection is really what it boils down to.


 Just to add onto that. If you use cheap connectors (like you get in an auto parts store) and use the typical crimping tool, those have a pretty good chance of failing. If you have a nice high end crimper and connectors then those are really good connections and work great. Since most people can't justify spending the money to go with a high end crimper and connectors to go with it (because they do maybe two connections per year), then they are left with what they have sitting around. I find that since you are dealing with those cheap connectors, then spending your time cutting off whatever plastic thing they have around the area the wire goes into, sticking a wire into the connector, crimping it, then backing up that with properly soldering it, then covering that area up with heat shrink (Harbor Freight even sells nice boxes of marine shrink wrap with glue in it really cheap) will work like a champ.

We can go into the theory behind what is better but 99% of the home mechanics out there just don't have the proper stuff to do those awesome crimps. So, you have to find and alternate method is using the parts you have at the best you can.

If you want to learn about cheap connectors and crimping, go buy an RV or a trailer. It can be any, really expensive or dirt cheap, they all have the same garbage connections and within a month you'll be tracking down plenty of electrical gremlins. While you are removing panels fixing those connectors you see they use self tapping sheetmetal screws to attach various thin wood products. While you are cursing that second problem out, you'll be stumped by the plumbing you discover too.


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## KBATTPO (Jan 15, 2001)

I normally shy away from religious debates like for example the obvious advantages of the metric system etc because I value my time. However this time around I am going to make an exception to this rule because this particular case may not only benefit the folks who are willing to listen and learn from 40+ years of this EE experience but to avert a potential disaster like a car fire.

The switch in the pictures below came out of a Ford Econoline van. In that particular primitive hunk of iron on wheels the HVAC fan motor is fed with several amperes of current(!) directly from the battery(!) via the speed control switch(!). Needless to say, the connection/disconnection arcing created a lot of heat => oxidising the contacts even further => further increasing the contact resistance => further exacerbating the connection/disconnection arcing to the point that the heat had burnt a hole in one side and caved in the adjacent side of the switch. 

To add insult to injury the spade connectors inside its plug were crimped rather than soldered thus the point of contact was exposed to moisture in the air. Summers here in Philly are hot and humid so Copper has been oxidising over the years => the resistance of the crimped connection has been increasing. Since the motor was drawing a lot of current this resistance has been causing quite a bit of heat at the crimped joint => which eventually lead to the complete meltdown and falling apart of the plastic housing. It was only a matter of time for the power wire and ground to come into contact. The housing had crumbled into pieces the moment I touched it. I don't need to explain what a ticking bomb that was.

Now, I understand that no sane engineer would specify and no sane accountant would approve connector soldering over crimping at a car factory but we, the DIY'ers, don't need to abide by their rules. We are fixing our cars to be reliable and safe for us and our families to use; mass production automation and time/cost savings are of little concern to us. 2Cu + H2O + CO2 + O2 → Cu(OH)2 + CuCO3 belongs on monuments, not on electrical contacts. Stay safe, folks; don't crimp - solder!

I took some self explanatory pix for your amusement.


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## KBATTPO (Jan 15, 2001)

Decided to add a few more pictures relevant to the subject.

Below are some pictures taken as I was documenting the replacement of the OE fuel pump with a high output Bosch -044 pump in my S6.

In each of the pictures below one wire still has the the badly oxidised OE crimped connectors on both ends, the other wire has already been cut and the new terminals (ring and spade) have been soldered onto it.




















And here is a picture of the lousy OE crimp joints on the spade connectors that connect the fuel gauge sender to the instrument cluster in my wife's Allroad. These little buggers have been causing erratic fuel gauge reading for 12(!) long years. The hapless service advisors at the dealership that sold me the car replaced three(!) instrument clusters under warranty yet the problem was still there. I would tell them to look into the fuel sender instead but they would not listen - to them I was a stupid Mr.Consumer - what could I possibly know about cars? I eventually gave up on this and learned to never let the fuel level fall below the last 0.25 of the tank. Last summer the fuel pump died so finally I had a chance to address this problem that had been plaguing my car since new. Needless to say, I found the problem exactly where I expected it to be - at the badly oxidised crimp joints. 










Sometimes in a pinch I have to use crimp connectors like in this particular case. In such cases I use the special crimp connectors that are made out of heat shrinkable plastic with glue inside. They form a permanent hermetic seal around the crimp joints shielding them from the elements. 



















At about a buck a piece they are rather expensive, take a bit of time to install (comparable with soldering) and when cooled down they make for rather stiff and long clumsy wire splices - hence I tend to avoid them whenever possible. IMO nothing beats soldering, however sometimes soldering is not an option so you use what you can to get the job done.


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## shreddaddy (Oct 11, 2021)

This is on my list of things to do. I currently read temps through my scan gauge which works okay. I take it you have replaced the OEM transmission cooler?


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## KBATTPO (Jan 15, 2001)

That's correct.


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## Endopotential (Dec 25, 2021)

This is a great thread. Thanks for posting the original instructions KBATTPO!

I've been trying to order the same New South Performance gauge all year, but they've been sold out and won't answer the phone. Luckily I found essentially the same product from GlowShift for only $55. It has 7 different lighting options, and the dark indigo is a good match for the stock dash lights.
Amazon.com 

To add to the repository of knowledge here for the next home mechanic - it was the first time I worked on this part of the car, so having these pics would have helped.

The transmission plug you're looking for is located in the front left edge, below the starter and to the left of the plastic inspection tube. There's a small plastic bracket in front , held on by a 10mm bolt that you have to temporarily remove, which threw me off for a bit. In the picture below, the silver Allen key points to the actual port you're looking for behind that bundle of black conduit.










The auxiliary port you're looking for is kinda hard to see from below the car. I was looking for a bolt with a hexagonal head, and was a bit dismayed when I couldn't find it. Turns out it's got a flat head with a recessed 5mm Allen hex hole.










Now I can drive with some more piece of mind being able to keep an eye on the transmission temp. Thanks forum!


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## Butch Milam (5 mo ago)

KBATTPO said:


> Next we need to install the temperature sender into the transmission. I found that the M10x1 port for the service plug (denoted as item #12 in the ETKA illustration below) is a perfect place for it:
> 
> 
> 
> ...


Installing a real guage the way you have is a fantastic idea. It will eliminate all the burdens of monitoring with OBD2. (No phone/bluetooth required, no OBD2 reader, no drained battery when forgeting to disconnect it, etc.) I am going to try it. Your description and photos of the installation are awesome. Precise, articulate, and easy to follow. I wish all posts were this well done. Thank you!


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## KBATTPO (Jan 15, 2001)

Glad I could help. I post those lengthy nerdy picture heavy write-ups in hopes that they might help somebody in the future.


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## Butch Milam (5 mo ago)

KBATTPO said:


> Glad I could help. I post those lengthy nerdy picture heavy write-ups in hopes that they might help somebody in the future.


They certainly do help. Keep them coming!


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## Butch Milam (5 mo ago)

Butch Milam said:


> They certainly do help. Keep them coming!


KBATTPO,
I am getting ready to jump in and try your trans temp gauge install. I have a couple questions for you (hope they're not too dumb)
1. My Eurovan has already had a trans fluid dipstick added. I am not sure where it enters the transmission. Do you think it could using the service port 12 where the trans temp sensor will be going? In other words, are there other usable service ports that can accommodate both the dipstick and the temp sensor? I realize I need to get under it and check it out, but I thought I'd ask, in case you know.
2. Since I don't have a die set and would probably muff up trying to re-thread the sensor, do you think a 1/8 Inch - 27 NPT to M10x1 adapter for the sensor would work? Do you know how deep into the transmission the sensor probe must extend?
3. I assume the belly pan must come off to get to the service port to install the sensor?

Thanks for any help,
Butch


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## Butch Milam (5 mo ago)

KBATTPO said:


> Glad I could help. I post those lengthy nerdy picture heavy write-ups in hopes that they might help somebody in the future.


KBATTPO,

I assume the belly pan must come off to get to the service port to install the sensor?


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## KBATTPO (Jan 15, 2001)

Butch Milam said:


> 1. My Eurovan has already had a trans fluid dipstick added. I am not sure where it enters the transmission. Do you think it could using the service port 12 where the trans temp sensor will be going? In other words, are there other usable service ports that can accommodate both the dipstick and the temp sensor? I realize I need to get under it and check it out, but I thought I'd ask, in case you know.


No. I also have added the dipstick - it's a totally different port.


> 2. Since I don't have a die set and would probably muff up trying to re-thread the sensor, do you think a 1/8 Inch - 27 NPT to M10x1 adapter for the sensor would work? Do you know how deep into the transmission the sensor probe must extend?


I did not test it, but this should be irrelevant. The sensor will still be awash with fluid therefore it will be showing the temperature.


> 3. I assume the belly pan must come off to get to the service port to install the sensor?


Correct.


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## Butch Milam (5 mo ago)

KBATTPO said:


> No. I also have added the dipstick - it's a totally different port.
> 
> I did not test it, but this should be irrelevant. The sensor will still be awash with fluid therefore it will be showing the temperature.
> 
> Correct.


Awesome. Once again, thank you. Much appreciated.


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