Does the car have to be running to use the car charger for my cellphone?
NO. Just make sure there is power there, may have to put the key on Acc, but the draw is very low, it does not need to be running
it will not charge the cell phone unless the car is turned on- look at your charger light- when you shut the car off, the light on the charger shuts off too, so it is NOT charging if that light is off- most GM cars are like that.
Oh the good old days of cigarette lighters. They ran w/o the key in the ignition. The plug in in the dash has to have the key in and turned to acc. I have not checked the rear plug in yet, and it my be the same as the front. Perhaps this helps in not burning the electronics of the vehicle out due to a bad charger shorting out or what is being used sending a reverse current to mess the computers up. My 2005 Buick had the plug-ins wired to be used all the time, running or not.
Looking for a Used Terrain in your area?
CarGurus has 34,926 nationwide Terrain listings starting at $5,700.
Search GMC Terrain Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
GMC Terrain Experts