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Captiva
   
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Liftgate Release 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

Rear Closure Relay Switch B+

2

2

--

--

Liftgate Release Switch Signal

B2494 02

1

1

--

Rear Closure Relay Control

B3265 00

2

2

--

Liftgate Latch Control

2

2

2

--

Liftgate Latch Ground

--

2

--

--

Tailgate Release Switch Ground

--

1

--

--

1. Liftgate Release Switch Malfunction

2. Liftgate Release Malfunction

Circuit/System Description

The tailgate switch is an input to the BCM. The BCM supplies battery voltage to the signal circuit and when the tailgate switch is activated the signal circuit voltage goes low. The BCM controls the tailgate latch assembly through the REAR CLOSURE relay. When the tailgate switch signal is activated, the BCM enables the REAR CLOSURE relay by applying battery voltage to the tailgate relay circuit and the relay is energised when the BCM grounds the REAR CLOSURE relay control circuit. When the relay is energised battery voltage is supplied to the tailgate latch assembly through the tailgate latch control circuit.

Diagnostic Aids

Before testing can be performed, the tailgate must be opened.

Reference Information

Schematic Reference

Liftgate Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Rear Hatch/Gate 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, observe the scan tool Int. Boot/Liftglass Sw. parameter while pressing and releasing the tailgate release switch. The parameter should change between Active and Inactive
    2. ⇒If the parameter does not change, refer to Tailgate Release Switch Malfunction.
  2. Command the tailgate release by pressing the exterior tailgate switch. The tailgate latch assembly should release the tailgate.
    3. ⇒If the tailgate latch does not release the tailgate, refer to Tailgate Release Malfunction.

Circuit/System Testing

Liftgate Switch Malfunction

  1. Ignition OFF, disconnect the wiring harness plug at the tailgate release switch.
  2. Test for less than 1.0 Ω between the ground circuit terminal 1 and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Int. Boot/Liftglass Sw. parameter is Inactive.
    4. ⇒If not the specified parameter, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the BCM.
  4. Install a 3A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool Int. Boot/Liftglass Sw. parameter is Active.
    5. ⇒If not the specified parameter, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM
  5. If all circuits test normal, test or replace the tailgate release switch.

Tailgate Latch Malfunction

  1. Ignition OFF, disconnect the REAR CLOSURE relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.
    3. ⇒If the test lamp illuminates, test the control circuit for a short to voltage.
  3. Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  4. Disconnect the wiring harness plug at the tailgate latch assembly.
  5. Test for less than 1.0 Ω between the ground circuit terminal 3 and ground.
    6. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Connect the wiring harness plug at the tailgate latch assembly.
  7. Connect a 10A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the tailgate latch assembly is activated.
    8. ⇒If the tailgate latch assembly does not activate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the tailgate latch assembly.
  8. Connect a test lamp between the control circuit terminal 85 and ground.
  9. Command the tailgate latch to release by pressing and releasing the tailgate release switch. The test lamp should turn ON and OFF when changing between the commanded states.
    10. ⇒If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, 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 the circuit tests normal, replace the BCM.
  10. Connect a test lamp between the control circuit terminal 86 and B+.
  11. Command the tailgate latch to release by pressing and releasing the tailgate release switch. The test lamp should turn ON and OFF when changing between the commanded states.
    12. ⇒If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
    ⇒If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM
  12. If all circuits test normal, test or replace the REAR CLOSURE relay.

Component Testing

Liftgate Latch Assembly

  1. Ignition OFF, disconnect the wiring harness plug at the tailgate latch assembly.
  2. Install a 10A fused jumper wire between the control terminal 6 and 12V. Install a jumper wire between the ground terminal 3 and ground. Verify the release actuator activates.
    3. ⇒If the actuator does not perform as specified, replace the tailgate latch assembly.

Liftgate Release Switch

  1. Ignition OFF, disconnect the wiring harness plug at the tailgate release switch.
  2. Test for infinite resistance between the signal terminal 2 and the ground terminal 1 with the switch in the open position.
    3. ⇒If not the specified value, replace the tailgate release switch.
  3. Test for less than 2.0 Ω between the signal terminal 2 and the ground terminal 1 with the switch in the closed position.
    4. ⇒If greater than the specified range, replace the tailgate release switch.

Relay Test

  1. Ignition OFF, disconnect the REAR CLOSURE relay.
  2. Test for 60-200 Ω between terminals 85 and 86.
    3. ⇒If not within the specified range, replace the relay.
  3. Test for infinite resistance between the following terminals:
    4. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
         ⇒If not the specified value, replace the REAR CLOSURE relay.
  4. Install a 3A fused jumper wire between relay terminal 85 and 12V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 Ω between terminals 30 and 87.
    5. ⇒If greater than the specified range, replace the REAR CLOSURE relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Relay Replacement : Within an Electrical Center → Attached to Wire Harness
    •  Liftgate Catch Replacement
    •  Tailgate Outside Handle Replacement
    • Control Module References for BCM replacement, setup and programming
   


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