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Discussion Starter #1 (Edited)
I have finally got the conversion up & running to a point where I am very happy with the performance, but I'm still left with a couple of niggly little faults.
The first is probably simple & just needs me to spend some time tracing wires & playing with the fluke, but the temp gauge doesn't work. It worked fine in the donor car & the dash worked fine with the ABL so the chances of it being a sensor are pretty slim I think. Does anyone have a wiring diagram for this?

The second & by far the most annoying/frustrating is the accelerator dropping out. This only seems to happen at first start up & could happen 5-6 times & then clear. If I flick the ignition off & straight back on again, it reappears instantly! Once the van is warmed up, it stops doing it. I have taken the brake switches apart & they seem fine. I'm a bit beaten by the fact it only does it half a dozen times when cold & then clear.

Anybody come across this before?
 

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Hello,

as far as the temperature gauge goes, you should have a 4-pin sensor on the head - one wire goes to the temp gauge, the other goes to the ECU. I may be wrong about wire colours, but on mine it's a yellow/red wire to the temp gauge, and then the brown green wire must be earthed. The other side of the 4-pin is the ECU connection which are brown/blue and blue/brown.

I had the problem you are describing with the accelerator - in my case it was the brake pedal switch, the brake light wire and the clutch switch that was the problem. Do you have a clutch switch? If not take the clutch pedal wire and earth it - on mine it's a white/red wire.

Failing that you may have a wiring problem with the potentiometer - the best and quickest way to find this is to find all the fault codes in vcds which should point you to any problems.

Hope that helps.
 

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Discussion Starter #3
Hello,

as far as the temperature gauge goes, you should have a 4-pin sensor on the head - one wire goes to the temp gauge, the other goes to the ECU. I may be wrong about wire colours, but on mine it's a yellow/red wire to the temp gauge, and then the brown green wire must be earthed. The other side of the 4-pin is the ECU connection which are brown/blue and blue/brown.

I had the problem you are describing with the accelerator - in my case it was the brake pedal switch, the brake light wire and the clutch switch that was the problem. Do you have a clutch switch? If not take the clutch pedal wire and earth it - on mine it's a white/red wire.

Failing that you may have a wiring problem with the potentiometer - the best and quickest way to find this is to find all the fault codes in vcds which should point you to any problems.

Hope that helps.
Thanks for replying. I'll pull it all apart again this eve. Colours sound familiar. Have you got the early or late dash clocks? I have the later blue clocks. Been looking for a diagram for the pins to make diagnosis a little easier.
Unfortunately I have no vcds working right now, need to clean re-install, so I'm stuck with the hand held fault code reader. Not the most reliable thing I've ever bought!I:
 

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Hello there,

I hope you sort it out - I've never had much luck with those hand held things but if you can get the codes off then that's useful. I'm afraid the tdi conversions I know are on the T3, but the principle is the same (at least for the temp gauge) whatever the clocks are although I don't have your pintouts sorry. In my experience the usual problem here is that the temp sender wire (brown/green) isn't earthed on the other side but if you have a more complicated problem with the clocks then I'm afraid I'm no use!

If the earth's not the problem, you could bridge those pins temporarily (pins 2+4 on the 4-pin connector on the coolant flange, ensuring pin 2 is earthed) with a smallish resistor and see if the temp gauge goes to full - crude but might indicate a faulty temp sensor.

Good luck with it!
 
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