Some GM vehicles have a Telematics fuse which includes power to the OnStar. For example, the Cadillac XTS has such a fuse (Fuse No. 20) in the instrument panel fuse box in the lower dash to the left of the...
Hi there. The OnStar system is hardwired into your ECU. Disabling the system without having the dealership reprogram the ECU can create serious electrical glitches; so I wouldn't recommend trying to do this.
