2003 Tahoe blows fuse on reverse (Page 1/1) tshark JUN 15, 07:34 AM Engine on or off, as soon as the shift lever hits reverse, the fuse shared with the overhead courtesy lights blows. Otherwise, the overhead courtesy lights work fine. Perhaps unrelated, but the radio won't keep it's time, either. I've tried disconnecting the radio, checked for other blown fuses, disconnected the harness going to the rear lights, and done some looking for shorts. I suspect either somewhere in the dash, or the switch on the transmission. Hank is Here JUN 15, 11:46 AM Could it be a floating ground issue? Check your ground connections to make sure they are tight and clean. carnut122 JUN 20, 09:13 PM I'm with you. Unplug the harness from the transmission and check all "non-grounded" contacts (on the tranny and the wiring harness) with a multi-meter for continuity to a known ground. If one tests out being grounded on the harness, I'd then check the back-up light fixtures to make sure only one of the bulb contact points is grounded. If the bulb holders check out, that leaves the wiring harness shorted to a ground. phreakboy4 JUN 22, 10:24 PM does it have a trailer hitch? some vehicles have a reverse wire in the 7 pin trailer plug which is a common spot for corrosion.