2006 Pontiac Grand Prix Owner's Manual - Page 305

When towing a trailer, the arrows on the instrument panel will flash for turns even if the bulbs on the trailer are burned out. You may think drivers behind you are seeing the turn signal when they are not. It is important to check occasionally to be sure the trailer bulbs are still working. The vehicle has bulb warning lights. When a trailer lighting system is plugged into the vehicle's lighting system, its bulb warning lights may not indicate if one of the lamps goes out. So, when a trailer lighting system is plugged in, be sure to check the vehicle and trailer lamps from time to time to be sure they are all working. Once the trailer lamps have been disconnected, the bulb warning lights can once again indicate if one of the vehicle lamps is out. Parking on Hills {CAUTION: You really should not park your vehicle, with a trailer attached, on a hill. If something goes wrong, your rig could start to move. People can be injured, and both your vehicle and the trailer can be damaged. But if the rig ever has to be parked on a hill, here is how to do it: 1. Apply the regular brakes, but do not shift into PARK (P) yet. 2. Have someone place chocks under the trailer wheels. 3. When the wheel chocks are in place, release the regular brakes until the chocks absorb the load. 4. Reapply the regular brakes. Then apply the parking brake, and then shift to PARK (P). 5. Release the regular brakes. Driving On Grades Reduce speed and shift to a lower gear before starting down a long or steep downgrade. If the vehicle is not shifted down, the brakes may have to be used so much that they would get hot and no longer work well. On a long uphill grade, shift down and reduce the vehicle's speed to around 45 mph (70 km/h) to reduce the possibility of engine and transaxle overheating. If the vehicle has overdrive, it may be driven in THIRD (3) instead of AUTOMATIC OVERDRIVE (D). 4-45