2003 Chevrolet Tahoe Owner's Manual - Page 352
2003 Chevrolet Tahoe Manual
Page 352 highlights
The seven-wire harness contains the following trailer circuits: @ Power Winches If you wish to use a power winch on your vehicle, only use it when your vehicle is stationary or anchored. Yellow:Left Stopflurn Signal DarkGreen:Right Stopnurn Signal Brown: Taillamps White: Ground LightGreen:Back-upLamps Red: BatteryFeed DarkBlue: Trailer Brake Step-Bumper Pad Your vehicle has a rear step bumper with a rear step pad at the center of the bumper. @ @ @ 0 If your trailer is equipped with electronic brakes, you can get a jumper harness (electric trailer brake control) with a trailer battery feed fuse from your dealer. This harness and fuse should be installed by your dealer or a qualified service center. If you will be using the bumper to tow a trailer, and your step-bumper has three cutout circles you must push out the center cutout circle to install the trailer ball. If you need to tow a light-duty trailer with a standard four-way round pin connector, you can also get an adapter. If your step-bumper has only one cutout circle, you will have to cut out the circle, then remove it to install the trailer ball. 4-73