# NAV Screen Rebooting Constantly



## Michaelmiracle (Nov 21, 2014)

*ZAB Screen Rebooting Constantly*

I know this is a known problem when the J523 reboots over and over and there is a black screen and no control of the functions. Also it doesn't shut off when the key is removed. I just started having this problem and have noticed it comes back to life off and on, and works for a time . I have tried to find a pattern to it and the most I can come up with is it is related to heat. Like, it works fine on cold startup on a cold morning. I even drove for 90 minutes at highway speed from a cold start and it worked perfectly the whole time. If I stop and restart the car after an hour or so, or drive around town at 30 mph, on a warm day, it acts up. 
The most anyone has tried to fix this is to replace the entire unit. The price of used ones is going for upward $600 US. And you still get a 16 year old unit. The price seems to be climbing as the buyers get less and the supply gets more, theoretically. There is a guy on Youtube that says he can repair them. He is in Serbia. There is another youtube video, from Russia possibly, that has no sound but the guy replaces a part in the electronics, that looks beyond my skill level.
In an effort to try the heat buildup theory I pulled out the unit and tested the small computer fan in the back of it. Sure enough it doesn't power on when connected to 12 volts. I am ordering a fan to try that as a first step. Does anyone have any experience to offer with repairing one of these?
Michael


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## Gabs08PHTN (Jan 6, 2011)

Hi Michael,
I had some similar issues some years ago when starting the car early in winter mornings. The culprit turned out to be the starter battery that was dead. I then replaced the starter battery with an AGM unit similar to the LHB and no more issues.
HOWEVER a few days ago the screen of my ZAB unit started to shut down by itself randomly. If I pressed the ON/DARK button it would come on again. In one of those instances I noticed that the screen was not warm, but hot to the touch and made me wonder if the cooling fan was faulty.
I then read a few posts here and in one of those was stated that some RDS radio stations can crash the ZAB unit, so as I do not listen to the radio much when I am driving, I changed the radio station and so far so good. 
I any case I am keeping an eye on the screen.
Should you find a suitable replacement for the fan, please let us know.

Gabriel

P.S. There is a firm in the UK called Cartronics that claims that can fix ZAB units.


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## Gabs08PHTN (Jan 6, 2011)

After 57 minutes of driving displaying the map screen it crashed twice today.
When I parked I could not hear the ZAB cooling fan running.
Does anyone know if it can be tested with VCDS?

Gabriel


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## Gabs08PHTN (Jan 6, 2011)

Back again...
After five hours resting in an underground car park, while driving back home after only three minutes of driving the ZAB screen went blank twice. 
Once at home I hooked up my computer and ran VCDS. No faults at all. I even ran all the output tests of the head unit, and everything was fine. I discovered that the cooling fan can be tested too, but again it spun faultlessly.
Right now I am :what:. Will wait and see if the screen goes blank in the following days.
By the way, our fellow member Chris Darby stated that his unit was repaired by Gerner Electronics (lasertrader.de).

Gabriel


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## Gabs08PHTN (Jan 6, 2011)

Update:
I have just removed the DVD navigation unit in order to check the optic fibre and electrical connections. The electrical and GPS antenna connections were sound, however the optic fibre corrugated sheath was somehow twisted anticlockwise with respect to the connector housing.
Upon closer inspection I noticed that the pair of optic fiber cables had been forced to slide between the two plastic halves that form the connector housing therefore presented a quite acute angle. Therefore I relocated the cables, locked the connector housing with two small cable ties and wrapped the sheath with insulating tape creating a wider angle for the optic fibre cables. Subsequently I ran VCDS and cleared the faults.
Lets hope for the best! 

Gabriel


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## tuut (Sep 13, 2016)

When I replaced my CD navigation unit, I accidentally ordered a DVD navigation unit.
This caused the ZAB to occasionally reboot.

Unplugging the CD player and DVD/CD navigation unit could be the cure if one of these turned out to be faulty.


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## 53PL-50AAA-VW611BAN (Feb 10, 2015)

tuut said:


> When I replaced my CD navigation unit, I accidentally ordered a DVD navigation unit.
> This caused the ZAB to occasionally reboot.
> 
> Unplugging the CD player and DVD/CD navigation unit could be the cure if one of these turned out to be faulty.


Did the DVD NAV work in your Phaeton? Could you use DVD map disks in it?

I know lots of NA Phaeton owners would love to run DVD NAV disks.

-Eric


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## Michaelmiracle (Nov 21, 2014)

Tried a new fan but it also doesn't work. May be on a thermostat. 
I didn't see a VCDS test for the fan. I saw one for the navigation cd unit. 

Now the ZAB has stopped being reachable by VCDS. And of course it's not reachable by the other functions of the car. 
I'm looking into a repair option. There is a service on eBay from Bulgaria that says they can repair it. They have good feedback rating but it's not covered by eBay protection because it's a service, I imagine. The price is listed as $275 with a 1 year warranty. I'm waiting to hear back about shipping costs, etc. 
I'll keep you posted of my experience, if it happens. 
Michael


Sent from my iPhone using Tapatalk


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## Gabs08PHTN (Jan 6, 2011)

Michael,
To test the fan you have to run the output tests of the head unit. It is the last one.
My ZAB unit is working fine so far. No more glitches thankfully.

Gabriel


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## tuut (Sep 13, 2016)

53PL-50AAA-VW611BAN said:


> Did the DVD NAV work in your Phaeton? Could you use DVD map disks in it?
> 
> I know lots of NA Phaeton owners would love to run DVD NAV disks.
> 
> -Eric


DVD navigation does not work in a CD navigation Phaeton.
Mine didn't anyway.


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## 53PL-50AAA-VW611BAN (Feb 10, 2015)

tuut said:


> DVD navigation does not work in a CD navigation Phaeton.
> Mine didn't anyway.


I didn't think so, but you did order a DVD NAV player by mistake. 

If it did work, it would keep the North American Phaeton NAV systems up-to-date longer since the latest CDs were from 2015.


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## bossplaya (Sep 13, 2015)

Hi, I have same problem. ZAB resets in loop about 3 seconds. What can it be?


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## Michaelmiracle (Nov 21, 2014)

Gabs08PHTN said:


> Michael,
> To test the fan you have to run the output tests of the head unit. It is the last one.
> My ZAB unit is working fine so far. No more glitches thankfully.
> 
> Gabriel



Gabriel
I received a used ZAB unit and it seems to work fine. I tried to do the output tests and all work except the fan does not turn on. My old unit wouldn't respond to the fan test either, even after I installed a new fan. Wondering if this fan test is for a newer model like yours or if anyone knows for certain that it works on the 2004 ZAB with 0188 software. I want to make sure the fan is not going to cause another failure.
Michael


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## Gabs08PHTN (Jan 6, 2011)

Michael,
I did the test with the engine running.
I hope it makes the trick!!!

Gabriel


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