GM Service Manual Online
For 1990-2009 cars only

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.

DTC Descriptors

DTC B396F 06: Liftglass Ajar Output Signal Circuit Short to Ground or Open

DTC B396F 0B: Liftglass Ajar Output Signal Circuit Current Above Threshold

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Liftglass Ajar Switch Signal

B396F 06

B396F 06

B396F 0B

--

Liftgate Window Latch Ground

--

B396F 06

1

--

1. Liftgate Ajar Indicator Inoperative

Circuit/System Description

The liftgate module (LGM) receives an input from the liftglass ajar switch. The ajar switch is normally open when the liftglass is fully closed. When the liftglass is opened, the ajar switch contact closes providing a path to ground. The driver information center (DIC) illuminates the Rear Access Open message when the liftglass is open.

Conditions for Running the DTC

System voltage to the liftgate control module must be 9-16 volts.

Conditions for Setting the DTC

B396F 06

The LGM detects a short to ground or an open/high resistance in the liftglass ajar signal circuit.

B396F 0B

The LGM detects a short to voltage in the liftglass ajar signal circuit.

Action Taken When the DTC Sets

    • When a short to ground condition is present, the Rear Access Open indicator will be continuously illuminated.
    • When an open or short to voltage condition is present, the Rear Access Open indicator will not illuminate when the liftglass is open or ajar.

Conditions for Clearing the DTC

    • The DTC will be current for as long as the fault is present.
    • When the fault is no longer present, the DTC will be a history DTC.
    • A history DTC will clear after 50 ignition cycles.

Reference Information

Schematic Reference

Release Systems Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Door Ajar Indicator 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

Ignition ON, observe the scan tool Liftgate Ajar Switch parameters while opening and closing the liftglass. The parameter should change between Active and Inactive.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the liftglass latch assembly.
  2. Test for less than 5 Ω between the ground circuit terminal 3 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify the scan tool Liftgate Ajar Switch parameter is Inactive.
  5. If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the LGM.
  6. Install a 3A fused jumper wire between the signal circuit terminal 4 and ground. Verify the scan tool Liftgate Ajar Switch parameter is Active.
  7. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the LGM.
  8. If all circuits test normal, test or replace the liftglass latch assembly.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the liftglass latch assembly.
  2. Test for infinite resistance between the signal terminal 4 and the ground terminal 3 with the switch in the open position.
  3. If not the specified value, replace the liftglass latch assembly.
  4. Test for less than 2 Ω between the signal terminal 4 and the ground terminal 3 with the switch in the closed position.
  5. If not the specified value, replace the liftglass latch assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Liftgate Window Latch Replacement
    •  Control Module References for LGM replacement, setup, and programming