GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Shift Lock Control Schematics

DEFINITION: Transmission shift lever does not lock in the PARK position with the ignition OFF.

1

Did you perform the Symptoms - Automatic Transmission Shift Lock Control tests and perform all the necessary inspections?

Go to Step 2

Go to Symptoms - Automatic Transmission Shift Lock Control

2

  1. Move the shift lever to the PARK position.
  2. Turn OFF the ignition.
  3. Press and hold the brake pedal.
  4. Attempt to move the shift lever out of the PARK position.

Does the shift lever move out of the park position?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

  1. Disconnect the park lock solenoid.
  2. Press and hold the brake pedal.
  3. Attempt to move the shift lever out of the PARK position.

Does the shift lever move out of the park position?

Go to Step 4

Go to Step 5

4

Inspect for poor connections at park lock solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 7

Go to Step 6

5

Repair the short to battery voltage in the A/T shift lock control switch supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 7

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6

Replace the park lock solenoid. Refer to Automatic Transmission Shift Lock Actuator Replacement .

Did you complete the repair?

Go to Step 7

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7

Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2