GMC Troubleshooting Questions? Ask a Mechanic for Answers
Hi there. I am Cam. With your issue, do you have anything aftermarket installed?If no then remove all the relays, one at a time and see if one makes it go out.
IF so then replace that relay. IF that does not change it, verify there is no wiring touching anywhere or shorted. One common place that causes this is attaching terminals in the dash fuse block or junction block at the drivers foot for aftermarket lights and such. Often normal terminals are used to connect to a battery feed and the terminal is too large and touches more than one causing this.