2011 Chevrolet HHR Owner's Manual - Page 146

If you forget to release your parking brake, a chime will sound and a warning message will be displayed when the parking brake is applied and the vehicle is moving faster than 5 mph (8 km/h). See DIC Warnings and Messages on page 4‑41. Notice: Driving with the parking brake on can overheat the brake system and cause premature wear or damage to brake system parts. Make sure that the parking brake is fully released and the brake warning light is off before driving. If parking on a hill and pulling a trailer, see Towing a Trailer (Automatic Transmission) on page 5‑31 or Towing a Trailer (Manual Transmission) on page 5‑37. Shifting Into Park (Automatic Transmission) { WARNING: It can be dangerous to get out of the vehicle if the shift lever is not fully in P (Park) with the parking brake firmly set. The vehicle can roll. If you have left the engine running, the vehicle can move suddenly. You or others could be injured. To be sure the vehicle will not move, even when you are on fairly level ground, use the steps that follow. If you are pulling a trailer, see Towing a Trailer (Automatic Transmission) on page 5‑31 or Towing a Trailer (Manual Transmission) on page 5‑37. 3-34