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Discussion Starter #1
Interesting fault in 1998 T4 2.5 petrol manual.
Whilst driving today I noticed that the Tacho was slowly creeping up and the speedo was staying constant. After a few minutes the speedo started to creep up as well. The traffic was doing a reasonably constant speed of 80 km/h but my speedo kept creeping up until it read 200km/h and the tacho was at 6000rpm. As I progressed the speedo and tacho went to full scale and remained at full scale.
The fuel gauge then started to move towards empty and the temp gauge started to climb. Once the fuel gauge got to empty it straight away started to climb with both temp and fuel ending at full scale.
With the ignition off the gauges initially stayed at full scale and after about 30 minutes started to decrease slowly. Which may indicate a capacitor or something discharging.
Anybody got any ideas on this one?
 

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Beardy Bus Driver
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have a search with google for vw t4 fuel gauge fault. iratic fuel gauge is common in earlier instrument clusters but don't know if this is the same thing.

good luck finding a solution.
 

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Discussion Starter #3
I had a read of the PCB mounted voltage regulator faults and the joints to resolder. Unfortunately my van is airbag equipped so that makes the task a little more difficult.
As well most of the descriptions refer to fuel gauge and temp gauge reading zero or erratic, not so much the speedo and tacho. I'm a little reluctant to tackle something that could go bang, so it may be a workshop fix.
 

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Discussion Starter #4
progress: getting the instrument cluster out was a piece of cake. I didn't need to remove the steering wheel, there was sufficient room to slide the cluster out. Now being a 1998 model, none of the descriptors here match my cluster. Part No 7DO 919 863A. I've dismantled the cluster as best I can but the gauges don't seperate from the PCB and I can't get the combination out of the housing. My manual although for post 1996 models doesn't cover this cluster either. Does anybody have any info on how this cluster comes apart?
 

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Discussion Starter #5
I have found the Solution.
My cluster does not have the voltage regulator which causes all of the problems in the early models. However, the problem is basically the same. The componentry at fault is a lot harder to get to and requires a lot higher skill level (than the earlier cluster) to rectify. Here are the steps required to repair:-
http://forums.tdiclub.com/showthread.php?t=268798
The faulty component is either the 'Dashboard Driver Elmos 10417A' or its adjacent capacitor (spec: 470uF 25V).
This will test out your soldering skills.
 

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Discussion Starter #7
So it's quite a challenge to remove and replace surface mounted components. But I did it and plugged the cluster in and it works fine. But I seem to have introduced some extra functions.
Now maybe my memory is failing but I don't recall the LCD displays remaining on when I remove the key and now the clock also has MFA 2 written beside it.
What the hell is MFA2 and where did this come from?
 
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