Operation CHARM: Car repair manuals for everyone.

Shift Interlock: Description and Operation

All vehicles are equipped with a brake shift interlock system. The brake shift interlock system prevents the shifting from PARK (the key is in RUN) unless the service brake is depressed. The brake shift interlock system consists of a brake shift lock actuator mounted at the base of the steering column. If the key is in RUN, the brake shift lock actuator continually runs unless the brake is depressed.