2005 Cadillac STS • 96,778 miles

My car won't shift outta park it doesn't do it all the time but its getting worst I took it to the shop and they said that it was replaced a pieces but I no that its during it again can you tell me what's wrong with it or what I need to do to get it fixed so that I can tell the auto service department exactly what's wrong with it
July 12, 2013.

The park lock actuator is powered through the brake light switch. When it doesn't work, check to see if the brake lights are working. If the aren't, check the brake light switch at the top of the brake pedal.