2005 A8L W12 Coolant Issues...
 

Hello all.

I have a 2005 (D3) A8L W12 which is giving me a coolant warning on the dash's mini-mmi. The temp gauge (on the dash cluster) stays all the way to the left on 'C' and does not move while the warning light flashes constantly (red coolant indicator) and the radiator fans run at full power!

I had the vehicle checked out in Traverse City, Michigan by Marathon Auto and they found no leak or any overheating (Code #: P0118). They said that the error seems to be with the dash computer as the coolant sensor is sending the correct information to the ECM (engine control module), but the data does not compute at the dash/instrument panel.

I've done numerous searches and cannot find much info on this exact issue with the W12 (I know we owners are few & far between). Any idea what I can do/look for? Is there a way to wipe out or re-boot the main computer?

Any help would be appreciated as I don't want to spend thousands at the dealer for a fix that could be a DIY. Lastly, any Michiganders (in the Detroit area) that can recommend a 'good/reasonable' & knowledgable mechanic that works with this particular car?

Thanks again!

Did anyone mention that it could possibly be the thermostat?