door does not lock after set to drive

Hi, this is Bo, an auto expert on RepairPal's Car Genius team! Well, that is very uncool of your HHR to not start in the cold! It sounds to me like a door lock actuator or door lock module has given you the cold shoulder and gone belly up. If the car locks and unlocks manually with the key, and starts normally, I'd say that's most likely your culprit. There's also the possibility of the door wiring harness have some damaged wiring causing no power to the door lock actuator/door lock module. I sure hope you can resolve this so you can warm that HHR up before you get in! BRRRRRR!!!! If you need any further advice or want help finding a trusted RepairPal shop in your area, please feel free to call us at 877-913-1554