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Diagnostic tools for Audi A4, 2002

Hello,

I am trying to solve a very difficult problem which most likely involves a foulty electronic module. The back-up lights are constantly on and passenger side mirror is tilted down as if the car was in reverse, regardless of the gear shift position. The car has a tiptronic transmision, by the way. My frastration is high, the car is disassembled to a large extend. Most of the electronic equipment and harnesses are exposed. I'm running out of options and I would like to obtain a diagnostic tool which would let me quiry the electronic modules, which are interconnected by CAM bus.

Can anyone help?

Thx, Jack

Reply to
Jacek
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Reply to
TonyJ

Nedavno Jacek napisa:

I do not know anything about tiptronic transmission, but on (older) cars there is a switch at a gearbox that turns on the back-up lights. In your case it probably gives a signal to the passenger side mirror to tilt down. Perhaps you might check that.

Reply to
me

I second that tool!

It might be a position switch on the transmission, but what does the dash indicator tell you? Does it always read 'R'? Might be a relay too! Not sure what the tip trans has. Have a repair manual?

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Reply to
dave AKA vwdoc1

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Thnk you for the advise guys. The problem is far more involved that this. A simple back-up light switch applies only to manual transmissions. This one has a "transmission range switch" which does a lot more. The switch is good. The signal coming out of the transmission is good. I believe there is a problem with the communicaiton between various modules. Something, somwhere is telling the "electrical power control module" to turn the back-up lights and tilt the passenger mirror. Something other than the normal signal coming from the transmission itself. Short of having various modules available and trying to troubleshoot them one by one, I'm stuck. I'm afraid a dealer will spend way too much time on it. I don't know how well and how quickly they can diagnose the problem.

Reply to
Jacek

So did you use a vag-com CAN tool to determine that the position switch on the transmission is working properly?

Thnk you for the advise guys. The problem is far more involved that this. A simple back-up light switch applies only to manual transmissions. This one has a "transmission range switch" which does a lot more. The switch is good. The signal coming out of the transmission is good. I believe there is a problem with the communicaiton between various modules. Something, somwhere is telling the "electrical power control module" to turn the back-up lights and tilt the passenger mirror. Something other than the normal signal coming from the transmission itself. Short of having various modules available and trying to troubleshoot them one by one, I'm stuck. I'm afraid a dealer will spend way too much time on it. I don't know how well and how quickly they can diagnose the problem.

Reply to
dave AKA vwdoc1

No, I don't have any diagnostic tools. I don't know what to get, there are so many of them out there. I did measure the voltage on the "reverse light" signal coming from the transmission switch and it reads "0 VDC" on all poositions except "10 VDC" on "R", which obviously is correct.

Reply to
Jacek

Sounds like you did some backprobing with all the plugs connected.

For a good tool to use...............go to

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the one that is highly recommended! A good repair manual, Bentley for the USA, is also highly recommended.

I am not familiar how that system works, but it might be a sticking relay or control module. Probably the ross-tech adapter could help you easily find the problem. ;-) There are also clones on ebay and others out there too that are cheap/cheaper, but the ross-tech adapter holds excellent resale value.

JMHO

Reply to
dave AKA vwdoc1

.

I just got the ross-tech type tool from e-bay. It was sent twice to a wrong address - ha, ha. Finally got it. It did show a number of issues that I have to spend more time researching. Seems like the Comfort Control Module is a major suspect, something I suspected from the beginning. I hope it will not put me in the poor house if I have to buy one.

Will keep you posted.

jacek

Reply to
Jacek

You can always post what you found (codes) with your new toy.......I mean tool!

"Jacek" wrote

snip

I just got the ross-tech type tool from e-bay. It was sent twice to a wrong address - ha, ha. Finally got it. It did show a number of issues that I have to spend more time researching. Seems like the Comfort Control Module is a major suspect, something I suspected from the beginning. I hope it will not put me in the poor house if I have to buy one.

Will keep you posted.

jacek

Reply to
dave AKA vwdoc1

Got a number of codes. Erased them all and that fixed a lot of problems. The original problem (Bac-up lights always on and passernger mirror tilted down) was caused by a faulty comfort module. Got another one (second hand) and.... all fixed. Now my pilot (remote control) doesn't work. I have to figure out how to syncronize it with the new module?!

Reply to
Jacek

either use your ross-tech type tool or 2 keys are needed. ;-)

Got a number of codes. Erased them all and that fixed a lot of problems. The original problem (Bac-up lights always on and passernger mirror tilted down) was caused by a faulty comfort module. Got another one (second hand) and.... all fixed. Now my pilot (remote control) doesn't work. I have to figure out how to syncronize it with the new module?!

Reply to
dave AKA vwdoc1

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