ALH accel pedal on AHU ECU?

Hey folks,

My 1980 Rabbit TDI project is coming along well. I got the detailed engine installed two weeks ago and it ran for the first time last Sunday .

One of the assumptions I made in the conversion was that an ALH accelerator pedal would work with the AHU ECU... Well even though the schematics seem to match, I may have a pedal compatibility problem as there is zero response from the pedal. And I don't have the original AHU pedal assembly.

Does anyone here have any details on pedal compatibility and if it possible to use the ALH pedal on an AHU installation? Any feedback would be helpful.

Thanks.

Actually, if anyone has the resistance value upper and lower bounds for each track in the AHU pedal, that would help me evaluate the ALH pedal and how I can match them up.

Thx...

its in the sticky

I may be out of line, but if you look at both wiring diagrams there is a subtle difference. Two wires need to be interchanged. I don't have the diagrams in front of me or remember which two they are.

rsxsr said:

I may be out of line, but if you look at both wiring diagrams there is a subtle difference. Two wires need to be interchanged. I don't have the diagrams in front of me or remember which two they are.

Click to expand...

There was a guy on the vortex that figured it out. He posted pictures and pin to pin wire swaps (he actually built a jumper harness)

It does work once wired properly, i have one on my 1z cabriolet! I had the advantage of both in my hand and metered them as i was doing it! rsxsr is correct it was swap of two wires, one function on the alh works backwards of the ahu, sorry though i don't remember which pair or color right now!

First post need HELP with swap put 2000 ALH into 2000 vr6 body need with help wiring harness. Do i need to change the whole interior wiring harness ?

G60ING said:

There was a guy on the vortex that figured it out. He posted pictures and pin to pin wire swaps (he actually built a jumper harness)

Click to expand...

Thanks guys... I'll check out the vortex for more info on this. I have started taking measurements on the harness pinout voltages to make sense of the electrical design. It would be great if someone has already done this...

When you have it wired correctly and functioning. You can see it working in the VAG-COM / VCDS software. I spent a lot of time trying to figure it out till I finally noticed the difference in the wiring diagram. The Bentley for that era turned the wiring into tiny little sections and navigating back and forth between the years, I kept missing it.

If you haven't found info yet! I have found my old notes by accident from when i did this! Trying to decipher notes from 3 years ago i get the following:
The A3 Pot
pin 1=white
pin 2=Pink
pin 3=brown
pin 4=gray
pin 5=green
pin 6=yellow

Not sure if those were harness side or pot side and i do remember a couple were different after the conenctor. Also don't recall if these are ohms or kohms:

pins 1 and 2 gave me decreasing value from 2.1 to 1.2
pins 1 and 3 gave me increasing value from 1.1 to 2.2
pins 2 and 3 gave me constant 1.2k ohms
pins 5 and 6 gave me open until WOT then 1k
pins 4 and 6 gave me 1k then opened after partial pedal

The mk 4 pedal gave me the following:
pin 2 yellow/green with pin 4 gray/blue gave me decreasing 1.8 to 1.0
pin 3 gray/red with pin 4 gray/blue gave me increasing 1.0 to 1.8
pin 6 brown/blue with pin 1 white/blue gave me open until WOT then 1k
pin 6 brown/blue with pin 5 gray/white gave me 1k then open after partial pedal
Hope it helps someone! I know its frustrating looking for it!