2014 GMC Terrain dead battery
after 6 days in garage, my 2014 GMC Terrain was dead. Nothing was left on. Dealer said it was all the onboard computer diagnostic checks that are done randomly which is causing the drain. After a jump from AAA, the radio or Nav system will not turn on.
I think your dealer is full o poop. If your battery is in good shape then your car should be able to sit for more than a week without problems. The radio issue might be a fuse and have your battery and alternator tested to make sure there are no problems.
There has been a lot of discussion on this very issue on this site, especially on the 2014 Terrains. I had that happen twice. AAA Jumpstarted and tested everything and said nothing was testing bad. GMC twice did full diagnostic runs and could not find any issues. Still have the factory battery also. I just was gone three weeks and when I came home, it started right off. Don't know what was done at the dealership, but after the second time, no issues. I asked if they reset anything or adjust or replaced anything and was told, no they did not. Tell your dealer several Terrain owners have experienced the same issues.
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