spoon2000

My 2000 A6 4.2 airbag control module is throwing a code as follows:

Address 15: Airbags Labels: 4B0-959-655-AI8.LBL
Part No: 4B0 959 655 F
Component: Airbag Front+Kopf 1002
Coding: 00304
Shop #: WSC 00000

1 Fault Found:
65535 - Internal Control Module Memory Error
00-10 - - - Intermittent

Can anything be done about this short of replacing the module? Bentley says no, but other websites seem to indicate that the module can be reset (by commercial vendors who you pay to do the magic).

FWIW the central lock system is also saying:

Address 35: Centr. Locks Labels: 4B0-962-258.LBL
Part No: 4B0 962 258 J
Component: Central Lock/Alarm D33
Coding: 15885
Shop #: WSC 02325

8 Faults Found:
01366 - Opened Due to Crash Signal
35-00 - -
01371 - Alarm triggered by Door Contact Switch; Driver's Side
35-00 - -
01572 - Alarm triggered by Door Contact Switch; Passenger Side
35-00 - -
01370 - Alarm triggered by Interior Monitoring
35-00 - -
01368 - Alarm triggered by Luggage Compartment Switch
35-00 - -
00955 - Key 1
09-10 - Adaptation Limit Surpassed - Intermittent
00957 - Key 3
09-10 - Adaptation Limit Surpassed - Intermittent
01574 - Alarm triggered by Door Contact Switch; Right Rear
35-00 - -

Could the crash signal reported by the central locks have affected the airbag module or vice versa? The car has not been in a wreck.

TIA.

Theresias

Resetting an airbag control module is not a legitimate action. Get a NEW one.

spoon2000

Why do you say that? I can understand your perspective if the car had been in an accident, but in this case it hasn't. I have seen a number of references on the web to the fact that modules can go into an "error" state for no apparent reason.

Theresias

...then this has a reason and it's not just doing that for fun. It could be damage or a failed self test due to under voltage (quite common in your model and I would expect that to be the case for you), it could also be a flaw in the control module memory or some other internal part which had failed.

VW/Audi specifically advice that one should only use new parts, used or reset parts are not legitimate. At the end it runs down to what you are willing to pay for one or more life. Personally I don't think saving a couple of hundred bucks is worth worrying if the used/reset component will work properly.

Last but not least, yes we have experience with people installing used parts after being advised differently. The most famous case ended up with the guy blowing all the airbags when installing his reset airbag control module - the guy ended up paying multiple times more for all the stuff than what a new airbag control module would have cost to begin with.

spoon2000

I understand your point completely about the safety aspect, so don't get me wrong. Safety was one of the reasons I opted for a 4.2 (heavier car, side-impact protection standard) over a lesser A6 and paid extra for stability control.

At the same time, the car has 60,000 miles, and it's not likely to be with me more than another year. If there is something causing the module to throw the code that's not the fault of the module, then buying a whole new module doesn't seem too logical to me, either.

It just seems odd that almost every other module on the car can be reset and will work fine, except this one, and I suspect Audi's lawyers have more to do with that than their engineers.

Regarding what VW/Audi advise, I (and I'm sure most Audiworld readers) take that under advisement but not as the final word. If we all listened exclusively to what VW/Audi had to say, we would never change our own light bulbs or oil, never put the car on a lift anywhere but at an Audi dealer, etc.

Just for curiosity's sake, will the module still function in the event of a real crash if it's storing the 65535 code?

And where are the reliable and price-competitive sources of new Audi airbag control modules?

Bracketracer

my suggestion is to call a few dealers to price them out. I run a shop, and replace a number of them each year, and buy directly from the local dealer. The liability of going through another source leaves me uneasy.

spoon2000

Thanks for that insight. I have actually called one dealer, and the quote was for $681.

Do you happen to know whether the last letter of the part number makes a major difference? I have 4B0 959 655 F but when the dealer put my VIN into his computer, it showed the correct part being 4B0 959 655 H. We had some back and forth about whether I really needed the "F" part, which is more difficult for the dealer to get but IS available. The dealer parts guy's speculation was that there was a very minor running change to the part at some point and that that's what the different last letter reflected.

Bracketracer

that sort of thing is somewhat typical of Audi/VW parts. I would probably go with their suggestion, especially if your VIN was used in ETKA to look it up.

Theresias

4B0-959-655-H does NOT support head airbags while 4B0-959-655-F does support head airbags. However, the new 4B0-959-655-F you should/will get is an updated version of your old one and will mostly have a different hardware/software version. This is just another reason why you should get a new one... There are reasons why they updated it.