scmalk

Hi All-

My 04 A8L continues to give us heardaches. This early VIN has been a real pain. We have a parasitic drain that leaves the battery dead if not driven daily. The dealership wants to replace the radio module, MMI module, new software, MMI control panel + more to the tune of $4456 and they will not guarantee that the problem will be fixed! They have discussed with the Audi Tech Line and this is their solution!

Does anyone have some direction for me?

New battery was also installed.

Thanks for any help that you can give me!

MP4.2+6.0

TSB 91-06-03 issued Feb. 8, 2006 says you do some diagnostics and eventually replace the radio due to a defective processor. Happens with ambient temps below 40 degrees per the TSB; applies to 2004's and 2005s up to a certain VIN. Says the issue is the defective radio wakes up the MOST/CAN bus, which is where the power suck then occurs. Is your situation such that you see those kinds of temps, maybe overnight?

Sounds like first you want to be sure they work through the TSB. The TSB does include looking at the MMI, radio and battery manager for error codes. No error codes though and I wouldn't be replacing parts other than the radio module if the TSB is on point.

Low tech: How about a basic solar charging mat on the back deck, like you can buy at a boating store or via catalog like West Marine? Kludgy yes, but certainly could save a lot of $$ if it is enough of a trickle charge (assuming your car is outside) and you don't care about the look.

tjf

Is it possible to pull individual fuses until you find out which system is causing the drain?

scmalk

Thank you both for the feedback!

While I live in a colder climate, the temperature has not been consistantly cold just yet.

That being said, the car is parked in the garage at night and iot doesn't get below about 50 degrees in the garage at night.

RKZ

Sorry to hear about your problem, bummer! Do you mind if I ask you where you had the battery replaced and what it cost?? DIY, Dealer, 3rd party? I've got an '04 like yours and I've just decided to keep it for another 2 year and bought an extended warranty. My experience tells me that 4-5 years is about all you can expect from an OEM battery and I'm thinking of replacing it early. Just curious about the cost.