Hi there, my 07 CTS has been perfect for years, however, recently I noticed a weird issue: when the AC is on, it doesn't heat or cool, but when you push 'AC off', it starts cooling or heating. This all happened after a recent oil change service at a local Cadillac dealer - don't know if they made some codes wrong there. Has anyone had such experience or any idea on this? Thank you!

 

@vivaamelia, since you have stated that you had the dealership perform maintenance on the vehicle and noticed this since then, I recommend contacting your local Cadillac dealership about this.

Michelle, Cadillac Customer Service

 

I'm far away from that dealership right now. Will visit them after get back. Is there anyway I can access the DTC code? I heard for 03/04 CTS you simply pressed the F1 and F6 button, but apparently not the case for 07 CTS. Any comments?