Never ending A3 dramas

[kenny0305]

Hi all,

Thanks for the help so far!

History: - Bought an S reg A3 in April last year. So far have replaced several parts of the suspension on the passenger side which now seems to be ok.

However, ECU blew about 2 months ago, according to the garage, this was a design fault. The wiring loom which comes up underneath the battery compartment had worn against the body causing several wires to short. These had to be replaced along with the crankshaft sensor and ECU.

Car has until now seemed to be running Ok. Now I have lost power to the electric windows, the sunroof and more importantly the central locking has stopped working. I cannot open the petrol cap which effectively means I am grounded.

So far, have stripped out half of the back trim to try to get to where I beleive the central locking pump is. I have checked all the fuses on a wattmeter and they all appear to be fine.

Checked a few other posts on this site which suggested fuse problems on fuse number 6 but this is ok.

My brother mentioned it could be a relay but being very much an amatuer I have no idea where to even look for this (or for that matter what it would look like!)

If anyone could give me a steer on this it would be much appreciated. As I have said, I am clueless on car issues so please, if you post, try to write it so an idiot could comprehend. This will save me posting back so regularly.

Many thanks.

 

[grathies]

Id say its gotta be your Convienience Control unit mate, need to see thru Audi as they have funny PR Codes that mean you need the right one (and would need to be programmed by Audi as far as I know)

Its a box that basically controlls your windows, central locking etc. They go on VAG cars quite alot

 

[Willber]

You can open the petrol cap manually mate, it tells you how in the manual!

'Open tailgate, remove right hand side trim (far right, the small one in the corner) pull actuator to release flap'

Hope that helps.

 

[kenny0305]

Cheers guys,

Managed to find the big red pull cord so now have fuel in the beast once more. Stripped it down today with friend to try to find relays. Removed front dash under steering wheel and removed four relays which looked ok, can see no damage to them but not sure how to test them if at all. Am I correct in thinking that the windows, sunroof and central locking all run through one of these relays? If so, does anyone know which one would likely be faulty? Also, if I had the car code read at the garage, would a convenience control unit fault show up?

Have just noticed a knocking sound coming from the exhaust now as well, just to add insult to injury. Think the filter in the catalitic convertor could be floating causing the exhaust to sound blown out.

Much more and this car will be making its final journey to the great scrappy in the sky.

Many thanks for the help once again lads.

 

[simch]

I would firstly get a proper vagcom check done of it. It should highligh the areas to look at. Otherwise you ciould be chasin g your tail forever.

Never heard of wiring shorting out neart he batery, never mind it then blowing the ECU....!??! ECU should be able to cope with shorting etc, after all, many sensors do this when they go faulty, ie short to earth and it is the ECU that reads this short and logs it as a fault! ONce the woring is sorted it should be ok.

Convenince module is a common fault on passats, as they can get water entering the cabin on pas side and getting into it, causing havoc! But not as common on S3/ a3; worth looking for water entry into the car, ie watermarks on soundproffing , dampness etc. But if it all loks ok, it may well be a more simple fault or even a fuse ! Drivers door module has been known to go wonky, but again Vagcome should tell you!

Good luck

 

[kenny0305]

Guys,

Sorry to be a pain. Looked at the car again this morning and took up the carpet on the front passenger side. It was soaking wet underneath. On closer inspection, I have a tiny hole above the centre post on the outside of the car. I will fill this today to stop it happening again.

However, decided to try and find the convenience control unit under the carpet. Told to look here by the incredibly helpful Andy at Inde Tech Milton Keynes. What I thought was the ccu was in fact the lateral speed sensor for side air bag. This was told to me by Technical Parts Service (Audi) Milton Keynes. I asked for a price and part no for convenience control unit only to be told my S plate A3 does not have one???? Not convinced by Audi parts gateway, dont suppose any of you guys have a part no or a picture of what the little badger actually looks like?

Got hold of an Audi schematic from the web which makes reference to a Convenience CAN but to be honest, its like reading heirohlyphics to me.

If anyone can give me a definitive area to look for this thing would be much appreciated. Once again, many thanks for the help lads.

Kenny

 

[kenny0305]

Gentlemen,

Success! Stripped out the central locking pump unit, only to find 2 wires corroded around the chocolate block plugging into the unit. Was quoted £229 + VAT for new unit. Decided to fix it myself. Little soldering, little drilling, unit is now in full working order. Also sealed the small hole in the car with some silicon so should be done and dusted now.

Would like to thank the guys who have helped me with my problems and for their patience with my naivety. Cheers fellahs, happy motoring

 

[Willber]

Sweet mate glad to hear you've sorted it!

 

[Clach]

well done mate....