Audi hazard lights stuck on.

[imamartian]

Hi can anyone suggest what might be wrong with my Audi A6? I went to work the other day and the hazard lights came on by themselves and stayed on (no flashing, just on!!). I had to stop and restart the car to make them go off... but after 30 seconds they came back on. It happened a few times until eventually they wouldn't go off at all.

Took it to the garage, they tried two new hazard light switches, but this did nothing. I then had to take out the fuse to stop them, but my indicators would flash very rapidly.

Took it back to the garage, and they said it was the alarm, and being factory fitted i'd need to go to the main dealer. So they took out the fuse to the alarm to disable it, and i'm now without alarm, central locking or electric windows....

Got up this morning, and the car had a flat battery.... jumped started it and drove around a bit, parked it up and the hazards came back on... so obviously not the alarm...

Anyone got any ideas at all?

 

[Mursal]

You will probably have to get it plugged in to read the fault codes. Likely to be a faulty sensor.

They put in a new flasher unit when they changed the hazard switch?

 

[imamartian]

You will probably have to get it plugged in to read the fault codes. Likely to be a faulty sensor.

They put in a new flasher unit when they changed the hazard switch?

They didn't mention a flasher unit. Would that make them come on for no reason?

Would it need to go to the main dealer for the plug in fault code thing?

 

[Mursal]

The flasher unit would be my next stop, especially when the alarm didn't cure it. Probably not the fault but worth checking.

No a good independent garage will plug it in to a fault code reader and tell you the fault codes. Or the required repair.

They are quite complicated, but very good build quality (Audi) so its just a matter of getting the fault. How old is your A6?

Is there anything else that may be a clue to the origin of the problem? Other electrical fault, lights not working, other work on the car, front impact etc?

 

[imamartian]

interesting you ask that... about 2 weeks ago, after a particularly rainy night, the passenger rear footwell was full (about 5cm) of water.... almost like a window was left open - but it wasn't . However, the garage mentions wires for the alarm under the carpet?

rain thing never happened before, or since... and i couldn't copy it with a hosepipe...?!

 

[iwaters]

interesting you ask that... about 2 weeks ago, after a particularly rainy night, the passenger rear footwell was full (about 5cm) of water.... almost like a window was left open - but it wasn't . However, the garage mentions wires for the alarm under the carpet?

rain thing never happened before, or since... and i couldn't copy it with a hosepipe...?!

This is your problem. It is very common. There are drian plugs in the plenum chamber (the bit where the battery and brake master cylinder are). These holes get blocked and so after a heavy raid the plenum chamber fills with water and flows into the cabin, via the pollen filter.

This obviously gives you a soaking wet passenger carpet but also thanks to some brilliant design causes an electrical item called the CCM (Convience Control Module) to get soaked as it is under the carpet on the passenger side.

This causes things like the hazzards to glow, windows to go up and down on their own and so on.

You need to pull the carpets back and make sure the box is dry. Try using a hair drier to really dry it out. The carpets and noise insulation are reasuringly thick so it is quite hard to get them up and access the CCM, try wedging a large piece of wood under them to keep them up.

Given that you have only had one flood hopefully you can dry the CCM out and your problem should go away. Otherwise if the connections have started to corrode you may have to get busy with a soldering iron, or worse a new CCM.

You will also need to fix the blocked holes, they are a bit difficult to get to, one is under the brake cylinder the other under the battery tray. You should be able get a long screwdriver in there to clean the holes.

I believe Audi did recall some of their cars over this matter and fitted modified plugs which don't block so easily. Although this may have only been in North America as I think there was a class action lawsuit over the issue. Might be worth speaking to the parts desk at your local dealer and they might be able to get the you new plugs. Otherwise just clean them out and check them regularly.

 

[Mursal]

At least now you know whats causing your problem. Not to easy to dry it out as the carpet and sound insulation will be a hefty bit of kit. Plenty of heat and newspapers

We sometimes have success with a small hard flexible hose (12-15mm diameter) for unblocking the gutters. Don't let it happen again as you may have even more trouble the next time. Keep her in or at least try and reduce the flow of water in the windscreen area until you get it sorted.

 

[albysenior]

agree fully with "iwater" also check the 3 or 4 multi plugs on the left hand side a pillar when ya take the carpet up as they corrode in the multiplugs
if ya catch it quick enough you can dry th ecu out

 

[imamartian]

Thanks all for for a comprehensive explanation. What i can't see is how to get the carpet up... it all seems fitted..?

 

[albysenior]

its not easy but take the trim off by the door /sill just clips off but they are tight ! then i belive a couple of twist off clips that hold carpet under dash,
this should just give enough room to get the ecu out, and dry floor out ...but its still tight.but easier than taking the whole lot out.

 

[imamartian]

its not easy but take the trim off by the door /sill just clips off but they are tight ! then i belive a couple of twist off clips that hold carpet under dash,
this should just give enough room to get the ecu out, and dry floor out ...but its still tight.but easier than taking the whole lot out.

thanks alby... would you consider it a diy job, or the job of an automotive electrician?

 

[albysenior]

have a go m8, its straight forward if ya just taking carpet up and taking ecu out to dry it out.
its just fiddly and tight under the carpet.

 

[imamartian]

have a go m8, its straight forward if ya just taking carpet up and taking ecu out to dry it out.
its just fiddly and tight under the carpet.

thanks mate, will give it a go at the weekend....

one other quick question..(or two.. ).. any idea how much for a new ecu? or how much for a mobile automotive electrician to come out and do it for me? (only ballpark...)...

 

[jonnyfishing]

If you do need an e.c.u. repair try here:- www.the-ecu-doctor.co.uk

 

[gregers]

1:try ebay for the ecu?
2:should be a lot cheaper then the dealer.