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Transmission Control Lever Malfunction

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Ignition

1

1

--

--

Control

1

1

2

—

1. Gear lever will not move from PARK with the brake pedal pressed.

2. Gear lever will move from PARK without pressing on the brake pedal.

Circuit/System Description

The stop lamp switch controls the shift lock solenoid by providing battery voltage to the shift lock control solenoid when the brake pedal is pressed. Ground is provided to the solenoid when the gear lever is in the park position.

Diagnostic Aids

If the automatic transmission shift lock control circuit is shorted to B+, the A/T shift lock solenoid will be inoperative. The vehicle will shift out of PARK without pressing the brake pedal.

Reference Information

Schematic Reference

Shift Lock Control Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Automatic Transmission Shift Lock Control Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the B103 Brake Lamp Switch.
  2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 1 and ground.
    3. ⇒If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
  3. Ignition OFF, connect the harness connector at the B103 Brake Lamp Switch. Disconnect the wiring harness plug at the M7 Automatic Transmission Shift Lock Actuator.
  4. Test for less than 1 Ω between the ground circuit terminal 4 and ground.
    5. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  5. Ignition ON, connect a test lamp between the control circuit terminal 6 and ground.
  6. Observe the test light while applying and releasing the brake pedal. The test lamp should turn ON and OFF when applying and releasing the brake pedal.
    7. ⇒If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, test or replace the B103 Stop Lamp Switch.
    ⇒If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the B103 Brake Lamp Switch.
  7. Test for less than 1 Ωbetween the control circuit terminal 1 and the control circuit terminal 3.
    8. ⇒If greater than the specified range, test the control circuit for a short circuit to ground or an open/high resistance.
    ⇒If all circuit tests normal, replace the M7 Automatic Transmission Shift Lock Actuator.

Component Testing
  1. Ignition OFF, disconnect the wiring harness plug at the M7 Automatic Transmission Shift Lock Actuator.
  2. Place the transmission lever in the park position.
  3. Test for less than 1 Ω between terminal 3 and terminal 4.
    4. ⇒If greater than the specified value, replace the M7 Automatic Transmission Shift Lock Actuator.
  4. Install a 10A fused jumper wire between the control terminal 6 and 12V. Install a jumper wire between the control terminal 7 and ground.
  5. The shift lock actuator should turn on.
    6. ⇒If the function does not perform as specified, replace the M7 Automatic Transmission Shift Lock Actuator.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Automatic Transmission Shift Lock Control Actuator Replacement

   


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