Had the same problem with my 2003 Tahoe. It's the aftermarket lights. The LEDs do not have enough, for lack of a better term, resistance in the bulb themselves. So, the car senses that you have the brakes on. Hence no CC. You can buy an online resistor for the wiring and it solves the problem. Can't remember the particular part. I owned the Tahoe in 2002-03. Had to get rid of it. It was a lemon. Beautiful vehicle but a rolling piece of crap. Replaced it with an 04 that never gave me any problems.