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 the Automatic Transmission Shift Lock Control Diagnostic System Check?

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. Turn OFF the ignition.
2. Disconnect the stoplamp switch.
3. Turn ON the ignition, with the engine OFF.
4. Pressed and hold the brake pedal.
5. 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

Connect a test lamp between the A/T shift lock solenoid supply voltage circuit at the auto trans shift lock control solenoid and a good ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 6

1. Inspect for proper automatic transmission shift lock control switch adjustment. Refer to Stop Lamp Switch Adjustment in Hydraulic Brakes.
2. 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 10

Go to Step 8

Inspect for poor connections at 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 10

Go to Step 9

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

Did you complete the repair?

Go to Step 10

--

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

Did you complete the repair?

Go to Step 10

--

Replace the automatic transmission shift lock control solenoid. Refer to Shift Control Lever Replacement in Automatic Transmission - 4L30-E.

Did you complete the repair?

Go to Step 10

--

Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2