Q: I have a 2007 Cadillac STS , the passenger door will not unlock with the fob or unlock from inside the vehicle controls , you have

Hi Ken. Thanks for contacting us tonight. What you are describing is commonly caused by an open or damaged electrical relay that operates the power lock function on your door. When the relay is stuck in an open position, it basically renders the electrical input portion of the door lock useless - which is why you can manually unlock. However, when the lock is unlocked, the relay sends power to the module to lock it. However, it is possible that there is an additional electrical glitch somewhere in between the door locks module and the door itself. It’s probably best to have a professional mechanic complete a power door inspection, so they can isolate the source of this problem and recommend or complete the right repairs.