420 - Your CAT is shot
520 - The VSS is shot or disconnected. it is accessed through the right wheel well and is mounted on top of the right output shaft housing.
412 - May be the cause of 410. There are two vacuum controlled check valves for the AIR system, one for each manifold. One of the switches controlling the valves is bad. Not sure which is A and which is B.
VSS
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Cadillac Owners Forum
4.8M posts
369.7K members
Since 2002
Cadillac Forums is the perfect place to go to talk about your favorite Caddys including the ATS, CTS, SRX, Escalade, LYRIQ, Vistiq, concept and future Cadillac models.