I've purchased garmin gps which used 12 volt power adapter. It seems my Mitsubishi gallant 2002 has two of them although they're of different shapes.
I'm not sure which one to use but either way neither one seems to be charing my gps when I plug in the adapter. Do I need to turn on the power to those adapters. Am I inserting the adapter incorrectly (new car owner here). Or are the adapters broken?

thanks