2007 GMC Savana Van Owner's Manual - Page 282

Maintenance When Trailer Towing Your vehicle will need service more often when you're pulling a trailer. See the Maintenance Schedule for more on this. Things that are especially important in trailer operation are automatic transmission fluid (don't overfill), engine oil, axle lubricant, belt, cooling system and brake system. Each of these is covered in this manual, and the Index will help you find them quickly. If you're trailering, it's a good idea to review these sections before you start your trip. Check periodically to see that all hitch nuts and bolts are tight. The seven-wire harness includes a 30-amp feed wire. Both harnesses come without connectors and should be wired by a qualified electrical technician. The technician can use the following color code chart when connecting the wiring harness to your trailer and trailer brake controller. Seven-Wire Harness • Light Green: Back-up lamps • Brown: Parking lamps • Yellow: Left stoplamp and turn signal • Dark Green: Right stoplamp and turn signal • Dark Blue: Use for electric trailer brakes • Red/Black Stripe: Trailer accessory • White (heavy gage): Ground wire Four-Wire Harness (Trailer Brake Controller) • Black: Ground • Red/White Stripe: Fused Battery • Dark Blue: Trailer Brake Feed • Light Blue: Fused Stoplamp/CHMSL Trailer Wiring Harness The optional heavy-duty trailer wiring package includes a seven-wire harness assembly at the rear of the vehicle and a four-wire harness assembly under the left hand side of the instrument panel. The seven-wire harness assembly is taped together and located in a frame pocket at the driver side rear left corner of the frame. 282