# Replaced instrument cluster, fuel gauge reads opposite



## Silver TT (Jan 26, 2015)

Hi Everyone,
I recently replaced my dashpod, but not everything is working properly. The speedometer was originally in miles and I wanted to change it to a dashpod in Km. 

When I adapted the new dashpod to the car via vagcom, the speedometer reading is correct but the fuel level is opposite (because the dashpod is coded to the opposite fuel level sender).
The 2 sender types are: 

Vehicles up to 05.02 
float at lower end position approx. 59 Ohms 
float at upper end position approx. 282 Ohms 

Vehicles as of 05.02 
float at lower end position approx. 282 Ohms 
float at upper end position approx. 59 Ohms

When I flash the new dashpod with the old dash’s eeprom the fuel gauge is correct, but the speedometer is out about 30% (because it is internally still coded to the miles/h dash).
I don’t believe there is a way to adapt the dashpod to the opposite fuel level sender, or change the speedo coding from miles to Km…
Flashing the dashpod with the cluster dump from a ’02 TT with a speedometer in Km is the only solution I can see… Is there anyone that could email me this file? 
Or does anyone have any other ideas?
Thanks!


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## Silver TT (Jan 26, 2015)

bump


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## lite1979 (Sep 9, 2005)

I think you're going to have to get your hands dirty on this one. From what I've read, the only way to solve the gas gauge problem is by switching the electronic leads at the sending units, which is explained very well here. You can then use the adaptation that gave your correct speedometer readings and your fuel gauge will be correct as well.


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## sciroccohal (May 4, 2005)

*I'm no expert*

There are a BUNCH a,b,c,d, e, f Dash cluster build codes...varying by the years....You will have problems if you put a D cluster into a C car etc. Different logic chip programming.


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## Silver TT (Jan 26, 2015)

The resistance in the circuit will not change by switching the terminals, the result will be the same.


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## lite1979 (Sep 9, 2005)

@silver:

If you read through the link I posted, you'll see detailed instructions on how to switch the resistance board on the sending units. The leads I'm referring to are internal to the unit, of course, and you're right that it's not a simple wire swap.


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## Silver TT (Jan 26, 2015)

sciroccohal said:


> There are a BUNCH a,b,c,d, e, f Dash cluster build codes...varying by the years....You will have problems if you put a D cluster into a C car etc. Different logic chip programming.


The clusters are physically the same with the exception of the speedometer scaling. For example, the mph dash reads 130 Km/h at 12 o'clock, and the Km/h dash reads 100 Km/h at the same location. If you copy the EEPROM from the original dash in the car and flash the new cluster with it, the build codes become irrelevant (assuming the speedo is in the same units). The install is super easy too, because you don’t need to "adapt" the cluster to the car. The odometer will read correctly, and the keys will still work. This is what I did, and that's why the speedo is out 30%. I found a back plate on eBay that takes care of the scaling difference, it's specifically designed to change a cluster from mph to Km/h, and I think that's the route I will go (the led's on my original cluster were done anyway). 

Alternatively (for anyone who's interested) if you adapt the cluster to the car you will need to change the mileage: set it to zero, and then use vag com to change it. I recommend the codecard tool; you will get a checksum error from cheap eBay crap :banghead:. You will also need to re-adapt the keys, all of which is explained on the ross-tech website.




lite1979 said:


> @silver:
> 
> If you read through the link I posted, you'll see detailed instructions on how to switch the resistance board on the sending units. The leads I'm referring to are internal to the unit, of course, and you're right that it's not a simple wire swap.


Thanks, I'm still not sure what you mean though? The link just shows how to remove the resistance board? 
I also checked the repair manual, and the resistance values above are for a front wheel drive vehicle. The AWD primary and secondary pump resistance values are different from each other as well. I guess I could find two resistance boards (for the primary and secondary pumps) from a later model TT, which is what you might be saying?


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## BeasTToftheEast (Sep 20, 2007)

I'm having a similar issue with my fuel gauge reading the exact opposite as well. This issue started when my fuel gauge sender sensor was replaced. Any idea what could be done to rectify this situation?


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## Silver TT (Jan 26, 2015)

Hey man, I think you really only have 2 options:

1) Replace the sensor again, with the correct version (they installed the wrong sensor). The fuel level sensors resistance values reversed in May 2002 according to my Bentley manual. Here's what is says for all wheel drive fuel level sensor resistance values:

Through 02/05
empty - 29 ohms
full - 147 ohms

from 02/05
empty - 147 ohms
full - 29 ohms

Left side of fuel tank

Through 02/05
empty - 27 ohms
full - 140 ohms

from 02/05
empty - 140 ohms
full - 27 ohms

2) If you have an ebay vag tacho cable you can flash the instrument cluster with a newer year TT EEPROM cluster dump. If you register on nefmoto there is a library you can download it from. You will likely have to try a few (The speedometer may be scaled differently - use an iphone speedometer app to verify the displayed speedometer speed with your actual speed). Your odometer will read whatever the persons did when they uploaded the cluster dump - or possibly zero if they had the correct cable to change it to zero before copying it - then you can use vag-com to set it to the correct mileage. Adapt the cluster and keys too....

I would go back to the shop...


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## Silver TT (Jan 26, 2015)

lite1979 said:


> @silver:
> 
> If you read through the link I posted, you'll see detailed instructions on how to switch the resistance board on the sending units. The leads I'm referring to are internal to the unit, of course, and you're right that it's not a simple wire swap.





Silver TT said:


> Thanks, I'm still not sure what you mean though? The link just shows how to remove the resistance board?
> I also checked the repair manual, and the resistance values above are for a front wheel drive vehicle. The AWD primary and secondary pump resistance values are different from each other as well. I guess I could find two resistance boards (for the primary and secondary pumps) from a later model TT, which is what you might be saying?


What do you mean by "switch the resistance boards"? Switch with what?


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## BeasTToftheEast (Sep 20, 2007)

Thanks for your input, I'll definitely be having the shop take a look at this again.


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