GottaAllroad

CEL light came on two days ago. Took it to dealer to pull codes and diagnose ASAP. Found fault code P0421 and insalled new catalytic converter sensor (PN: 1-4Z7-997-551-LX?).

Dealer then went to flash the ECM with KM01 CD (?). At 90% complete on flash, ECM (5052?) froze and wouldn't take the entire flash. Dealer replaced ECM and all was fixed.

No charge - all under some kind of Audi warranty (I'm no longer under 4/48 nor CPO warranty, so I don't know what coverage kicked in - the tech said something about 8/80?).

TIA for any help translating some of these details. I'm a month away from my VAG and Bentley so I can diagnose myself, do the 402, etc. - but for now I have to ask for outside help.

Cheers.

gragravar

not sure what was up with the ECM flash. Maybe someone else can join in on that one.

blackIIIroad

vacuum booster..others. The dealer flashes your ECU with the improved M version of this software and these fault codes tend to disappear. That's why your ECU has a LX at the end. X means replaced/eXchanged

uber_ar

The ECU and cats are covered under emmissions warranty (8/80)

Nappy

Will these dealer flashes mess up aftermarket (GIAC or APR) stuff??

blackIIIroad

Yes, new flashed software overwrites old...have to reflash apr...giac