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 , Body Control System Connector End Views or Automatic Transmission Related Connector End Views

DEFINITION: Transmission shift lever does not lock in the PARK position with the ignition ON and the brake pedal not pressed.

1

Did you perform the Auto Trans Shift Lock Control System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission Shift Lock Control

2

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

  1. Turn OFF the ignition.
  2. Install a scan tool.
  3. Ensure transmission shift lever is in the PARK position.
  4. Ensure brake pedal is released.
  5. Turn ON the ignition, with the engine OFF.
  6. With a scan tool, observer the brake to shift control status in the rear integration module (RIM) data list.

Does the scan tool display ON status?

Go to Step 4

Go to Step 8

4

  1. Turn OFF the ignition.
  2. Connect a test lamp between the automatic transmission shift lock control solenoid supply voltage circuit at the automatic transmission shift lock control solenoid and a good ground.
  3. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 5

Go to Step 9

5

  1. Connect a test lamp between the automatic transmission shift lock control solenoid supply voltage circuit and the automatic transmission shift lock control solenoid control circuit at the automatic transmission shift lock control solenoid.
  2. With a scan tool, command the brake to shift control ON and OFF several times while observing the test lamp.

Does the test lamp turn ON and OFF with each command?

Go to Step 7

Go to Step 6

6

Test the automatic transmission shift lock control solenoid control circuit for and open, short or ground. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 12

Go to Step 8

7

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

Did you find and correct the condition?

Go to Step 12

Go to Step 10

8

Inspect for poor connections at the harness connector of the rear integration module (RIM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 12

Go to Step 11

9

Repair the open in the automatic transmission shift lock control solenoid supply voltage circuit. Refer to Circuit Testing and Wiring Repairs.

Did you complete the repair?

Go to Step 12

--

10

Replace the automatic transmission shift lock control. Refer to Transmission Control Replacement or Transmission Control Replacement.

Did you complete the replacement?

Go to Step 12

--

11

Replace the rear integration module (RIM) Refer to Rear Integration Body Control Module Replacement.

Did you complete the replacement?

Go to Step 12

--

12

Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2