Audi ECU sitting on my desk...

[NickHuge]

Hi guys

I have a replacement ECU which i bought of Ebay sitting on my desk, same serial number, and only cost £25!
No doubt this will need coding but will it cause any damage if i just try and swap them to see if miraculously it doesnt?:confused:

[Sam]

It will need matching to the Instrument Cluster/Immobiliser.

It may fire up after swapping but it will die shortly after. VAG used to give out the codes for doing this, but now they tend not to.

It would be better to ask what your reason is for swapping the ECU and work from there. I presume you have access to VAG-COM already and have worked out that your ECU is dead/faulty.

Information regarding pairing or matching is here;

http://www.ross-tech.com/vag-com/cars/immobilizer2.html
http://www.ross-tech.com/vag-com/cars/Immo3-ecu-swapping.html

[NickHuge]

Ah superb quick response!

It's audi who have told me that the diodes have fried due to water getting in after a leak. It was the ECU which controls the windows, sits under the front passenger seat. my windows go up intermitently but then seem to go into safe mode as if they are overheating and go back down again...

[Sam]

Ah, sorry, I thought you meant the main ECU - we're discussing the CCM (comfort control module)

That should, but I don't know for sure, be a straight swap. I tricky job if reports are to be believed.

Best of luck to you.

If you're willing, I'd really appreciate it if you could document (pictures/words) the replacement process and post it up here. It's a very common problem and you'd be helping a lot of members.

[NickHuge]

I can certainly do this. ive got as far as isolating the CCM before so presumably it'll be a straight swap. matching serial number so fingers crossed, its taken me about 6 months to find the part cheap!

Thanks for your advice and I'll try it in daylight tomorrow!

[NickHuge]

Right I've just swapped the CCM and it is exactly the same as before. both front windows go down but dont like going up, get half way and then have a life of their own. rear drivers side window works fine apart from only goes down 2/3rds of the way, rear passenger side window doesnt move at all...

Any ideas now? (had a quick look behind one door panel and nothing looked too covered in dirt or anything)?

At least we know you can straight swap the CCM!

[Niall76]

I don't think it's an ECU problem.

I know that there are problems with little platic runner pieces on the bottoms of the windows (within the door). They're guides for the window. These get worn and tend to jam, thus your ECU thinks that something is stuck in the window (like an arm/fingers/dogs head etc) and goes down again - it's a safety thing. Also clean out the rubber seal channels - the one above the door, these get all sorts of dirt in them over time and won't help the smoothness of it all.

[NickHuge]

so should i get replacement runners for them do you think?

[Niall76]

I'd take the door card off and then check the window action going up. Then you'll be able to tell straight away if the little plastic inserts for the runners are indeed the offending items for sure.

I reckon they probably are - which is good as it's a cheap and easy fix.

Let us know how you get on

[Niall76]

Oh, and it's the little plastic pieces (you'll know exactly what I mean when you take the door card off) and not the runners. The runners will be fine (by runners I mean the metal channel).

[NickHuge]

cool, will i be able to check with the panel just removed slightly or do i need to disconnect the speaker/lock too, looks a bit daunting!

[Niall76]

I seem to remember that you only need to take out the little screws qhich hold the door card in place. I think it then sort of slides off. You won't need to disconnect any wires or the lock.

[NickHuge]

ok well ive taken a door panel off, the runners seemed fine, i oiled the track they run on, and still the same problem. i cant see any debris, and the fact the that one rear window goes down real fast half way and has no obstruction going back up, and the other doesnt work at all, makes me think it could be something e;lse? perhaps a power problem getting from the relay?