pacco1989

Hello all. I looked in a lot of post here but i didn't see exactly my problem so I am opening a new thread.
My car is A6 C5 2003, 2.5tdi AKE, 180hp, quattro, auto trans.
My problem with the ESP starts over a year ago. First the lamp goes on and with it the engine sound becomes little more growling and the rpms goes higher to around 1200. More commonly the lamp goes on while i was driving and most commonly it goes away itself in 10 or 15 seconds. Sometimes it stayed for a longer period but goes away itself again. The rpms goes back to normal in the next 10-15 seconds.
Lately my problems become more serious. The lamp starts to goes on more often and with it the rpms goes higher to around 1200 while the car is not moving. Along with those symptoms the auto transmission starts to not shift up correctly at all. It is like it slips and the rpm goes higher but without shift up. When i stop the car and wait for a couple of minutes and start it up again everything is ok for the next 10 minutes and after that the same thing.
I had transmission repair 2 years ago because of the torque converter. Everything else in the transmission was ok.

We run diagnostic and the Transmission component is clean but this two faults are in the ABS/ESP component:

18265 – Load Signal: Error message from ECU
P1857 – 35 – 10 – Intermittent

01119 – Gear recognition signal
35 – 10 – Intermittent

I start with checking under the passenger's carpet and the results was not good. There was moist under the carpet. I checked the ECU that stays there and inbox and the metal body were still not wet. Checked the drainage under the battery in order not to get flooded again. I cleaned up and dried everything but again the problem was not solved. I tried to clean the ABS sensors but again nothing happened.

Please if anyone has the same problems as mine and solved it just say where and what I should check. Thanks in advance.

Harleyguy

Although it may look like the moisture didn't get into the control module I suspect it did. Even a small amount of moisture that has since dried up could have corroded part of the circuit board enough to cause damage. This is pure speculation but a good bet. The symptoms you are having indicate the control module is not working properly. There was a post on here several months ago about a method to dry out the module. I recall it was posted by Ocles. They are an approved vendor on this site. There are also a few chemical baths that can be had from electronics suppliers that can be used for displacement of water in electronic devices.

ocles_inc

Here is the link to the article I wrote.
https://www.audiworld.com/forums/a6-...e-not-2918407/

If you don't see an improvement I sympathize. I also do sell used transmission control module units. While you're about it, please make a note of the part number, including the last letter or two. That can help you find the right replacement part, if you need to.

Good luck!

~Tanya

@Harleyguy Thank you for the referral.

pacco1989

Thank you. Will try this and come back with the result of it.

pacco1989

Is there any differens from where i will get the acetone if it is pure 100%. I think it doesn't matter if it is pharmacy or paint shop or pc store. Am i right?

pacco1989

Seems to be working guys. So far so good. After the bath there are no errors. The rpms are steady, esp does not go on and transmission works smoothly.
Thank you for the help.
SOLVED!

Harleyguy

Yep, that Tanya is a peach. really knows her stuff! :-)

ocles_inc

Hi guys,

@pacco1989 I'm so sorry I didn't answer your question in a timely way, but I'm delighted you got it going even so !! :-)
@harleyguy Thank you :-) I am indeed brilliant ... at involving brilliant people. my tech Katie gets the credit on the acetone bath idea. :-)

I love happy endings.

~Tanya