GM Service Manual Online
For 1990-2009 cars only

Problem

Action

The park/lock system has malfunctioned.

Inspect park/lock system, repair as necessary. Refer to Electronic Column Lock Module - Disassemble - Off Vehicle and Electronic Column Lock Module - Assemble - Off Vehicle .

The lock cylinder is damaged.

Inspect lock cylinder, replace as necessary. Refer to Ignition Lock Cylinder Replacement - On Vehicle .

The ignition key is damaged or worn.

Replace the ignition key.