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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2008 🢒 Cobalt 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 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

Shift Lock Control Solenoid Control Circuit

B2705 02

B2705 05

B2705 05

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Transmission Shift Select Switch (Park) Signal

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B2705 05

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Circuit/System Description

The body control module (BCM) controls the shift lock solenoid by providing battery voltage to the shift lock control solenoid. The BCM utilizes a smart driver to control the voltage supplied to the shift lock solenoid. The smart driver monitors the voltage and current flow of the control circuit.

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Ignition ON, while pressing the brake pedal, observe the scan tool Brake Lamp parameter. The reading should be ON with the brake pedal pressed.
    2. ⇒If not the specified parameter, refer to Stop Lamps Malfunction.
  2. Press the brake pedal, the vehicle operator should be able to move the shifter lever out of the park position.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the automatic transmission shift lock actuator.
  2. Ignition OFF, test for less than 1.0 ohm between the transmission shift select switch (park) signal circuit terminal B and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal A and ground.
  4. Ignition ON, command the scan tool BCM Brake To Shift Control output control ON and OFF. The test lamp should turn ON and OFF as commanded.
    5. ⇒If the test lamp is always ON, test the control circuit for a short to voltage. If all circuits test normal, test or replace the BCM.
    ⇒If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If all circuits test normal, test or replace the BCM.
  5. If all circuits test normal, test or replace the shift lock actuator.

Component Testing
  1. Install a 10A fused jumper wire between the control circuit terminal A and 12 volts. Install a jumper wire between the transmission shift select switch (park) signal circuit terminal B and ground.
  2. Listen for the solenoid to turn ON and OFF.
    3. ⇒If the function does not perform as specified, replace the shift lock actuator.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup and programming