Cadillac Seville / Cadillac Eldorado Forum Discussion, engine light.. quotes code 121... solution please in Past Cadillac Vehicle Discussion; i have a problem with the engine start and shut off automatically..
i have an engine light that shows quote ...
Forget the scan tool, go to the top of the Seville/Eldorado page, and read the "sticky" on how to pull DTCs. List any codes you may find, AND their definitions, here (there is a link within the sticky with definitions).
Interesting: your profile says 2004 STS, only the Seville SLS was available in '04. You do have a Cadillac Seville STS, and not an '05+ Cadillac STS right?
No such thing as a 2004 "STS" (Seville Touring Sedan) unless it is a 2003 that was shipped overseas and titled in the 2004 model year. The driver's door sticker will have a latest build date of 06/03 - all STS production ceased in mid-June of 03 while SLS continued to 12/03, 5 months into the "2004 model year".
The code and definition makes no sense whatsoever - you need to use the car's built-in code system. Codes will display as a system, number, and timing - as in P 0385 C = Powertrain - CKP sensor fault - Current.