GM Service Manual Online
For 1990-2009 cars only

The auto trans shift lock control (ATSLC) system prevents the driver from shifting out of the PARK position without simultaneously pressing the brake pedal. When energized, the ATSLC solenoid locks the automatic transmission control lever.

When pressure is applied to the brake pedal, the following actions occur:

    • The ATSLC solenoid is de-energized.
    • The ATSLC releases the automatic transmission control lever.