Schematic Reference: Shift Lock Control Schematics

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

Did you perform A Diagnostic System Check - Automatic Transmission Shift Lock Control?

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission Shift Lock Control

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 without pressing the brake pedal.

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

1. Disconnect the automatic transmission shift lock control switch.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. Probe the park neutral position switch park signal circuit of the automatic transmission shift lock control switch with a test lamp that is connected to a good ground.
5. With a scan tool, command the Brake to Shift Output ON and OFF.

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

Go to Step 4

Go to Step 6

1. Turn OFF the ignition.
2. Reconnect the automatic transmission shift lock control switch.
3. Disconnect the automatic transmission shift lock control solenoid.
4. Turn ON the ignition, with the engine OFF.
5. Probe the A/T shift lock control supply voltage circuit at the automatic transmission shift lock control solenoid with a test lamp that is connected to a good ground.
6. With a scan tool, command the Brake to Shift Output ON.

Does the test lamp illuminate?

Go to Step 5

Go to Step 7

1. Connect a test lamp between the A/T shift lock control solenoid supply voltage circuit of the automatic transmission shift lock control solenoid and the ground circuit of the automatic transmission shift lock control solenoid.
2. With a scan tool, command the Brake to Shift Output ON.

Does the test lamp illuminate?

Go to Step 10

Go to Step 11

Test the park neutral position switch park signal circuit of the automatic transmission shift lock control switch for a open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 8

Test the A/T shift lock control solenoid supply voltage circuit of the automatic transmission shift lock control solenoid for a open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 9

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Body Control Module (BCM) Programming/RPO Configuration and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 14

Inspect for poor connections at the harness connector of the automatic transmission shift lock control switch. 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 15

Go to Step 12

Inspect for poor connections at the harness connector of the automatic transmission shift lock control 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 15

Go to Step 13

Repair the ground circuit of the automatic transmission shift lock control solenoid. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 15

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Replace the automatic transmission shift lock control switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes.

Did you complete the replacement?

Go to Step 15

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Replace the automatic transmission shift lock control solenoid. Refer to Automatic Transmission Shift Lock Actuator Replacement .

Did you complete the replacement?

Go to Step 15

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Important: After replacement of the BCM perform the set up BCM procedure for the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 15

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Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2