GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Shift Lock Control Schematics

Connector End View Reference: Shift Lock Control Connector End Views or Lighting Systems Connector End Views

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. Turn ON the ignition, with the engine OFF.
  2. Apply the parking brake and block the wheels.
  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 3

Go to Testing for Intermittent Conditions and Poor Connections

3

Connect a test lamp between the automatic transmission shift lock control input signal circuit at the harness connector of the automatic transmission shift lock control module and a good ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 4

4

Inspect for poor connections at the harness connector of the automatic transmission shift lock control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 7

Go to Step 6

5

Repair the short to voltage in the automatic transmission shift lock control input signal circuit. Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

Go to Step 7

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6

Replace the shift lock control module. Refer to Shift Lock Control Module Replacement .

Is the repair complete?

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 3