Operation CHARM: Car repair manuals for everyone.
Home >> Chevy Truck >> 2008 >> HHR L4-2.2L >> Repair and Diagnosis >> Body and Frame >> Locks >> Testing and Inspection >> Symptom Related Diagnostic Procedures >> Liftgate Release Inoperative

Liftgate Release Inoperative



Liftgate Release Inoperative

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



Diagnostic Fault Information






Circuit/System Description

The liftgate can be released by pressing the liftgate touchpad located in the handle above the license plate. All doors must be unlocked, the transaxle must be in park or a vehicle with a manual transaxle, the vehicle must be stationary for the liftgate to release.


Pressing the liftgate release switch closes a contact providing a ground for the liftgate release switch signal circuit. The body control module (BCM) will detect the voltage drop and command voltage to be supplied to the liftgate release relay control circuit thus energizing the L/GATE RELSE relay which provides voltage to the release actuator releasing the liftgate.


Reference Information
Schematic Reference

Release Systems Schematics (Release Systems Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Rear Hatch/Gate Description and Operation (Description and Operation)
Electrical Information Reference

* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Circuit Testing (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information


Circuit/System Verification

1. Ignition ON, observe the scan tool Liftgate Release Sw parameter while pressing and releasing the liftgate release switch. The parameter should change between Active and Inactive.

• If the parameter does not change, refer to Liftgate Release Switch Malfunction.

2. Command the liftgate door latch to release by pressing the liftgate release switch. The liftgate door latch should release the liftgate.

• If the liftgate door latch does not release the liftgate, refer to Liftgate Release Malfunction.




Circuit/System Testing


Liftgate Release Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the liftgate release switch.
2. Test for less than 1 ohm between the ground circuit terminal D and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify the scan tool Liftgate Release Sw. parameter is Inactive.

• If not the specified parameter, test the signal circuit terminal B 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 B and ground. Verify the scan tool Liftgate Release Sw. parameter is Active.

• 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 liftgate release switch.



Liftgate Release Malfunction
1. Ignition OFF, disconnect the L/GATE RELSE relay.
2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.

• 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.

• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

4. Ignition OFF, disconnect the harness connector at the liftgate door latch.
5. Test for less than 1 ohm between the liftgate door latch ground circuit terminal 3 and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

6. Connect the harness connector at the liftgate door latch.
7. Ignition ON, connect a 20-A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the liftgate door latch is activated.

• If the liftgate door latch does not activate, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the liftgate door latch.

8. Connect a test lamp between the control circuit terminal 86 and B+.
9. Command the liftgate release ON and OFF by pressing and releasing the liftgate release switch. The test lamp should turn ON and OFF when changing between the commanded states.

• If the test lamp is always OFF, test the control circuit for an open/high resistance.
• If the test lamp is always ON, test the control circuit for a short to ground.

10. Connect a test lamp between the control circuit terminal 85 and ground.
11. Command the liftgate release actuator ON and OFF by pressing and releasing the liftgate release switch. The test lamp should turn ON and OFF while changing between the commanded states.

• 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.

12. If all circuits test normal, test or replace the L/GATE RELSE relay.



Component Testing


Release Actuator, Door Latch - Liftgate
1. Ignition OFF, disconnect the harness connector at the liftgate door latch.
2. Install a 20-amp fused jumper wire between the control terminal 1 and 12 volts. Install a jumper wire between the ground terminal 3 and ground. Verify the release actuator activates.

• If the actuator does not perform as specified, replace the liftgate door latch.




Liftgate Release Switch
1. Ignition OFF, disconnect the harness connector at the liftgate release switch.
2. Test for infinite resistance between the signal terminal B and the ground terminal D with the switch in the open position.

• If not the specified value, replace the liftgate release switch.

3. Test for less than 2.0 ohms between the signal terminal B and the ground terminal D with the switch in the closed position.

• If greater than the specified range, replace the liftgate release switch.




Relay Test
1. Ignition OFF, disconnect the L/GATE RELSE relay.
2. Test for 60-180 ohms between terminals 85 and 86.

• If not within the specified range, replace the relay.

3. Test for infinite resistance between the following terminals:

* 30 and 86
* 30 and 87
* 30 and 85
* 85 and 87


• If not the specified value, replace the relay.

4. Install a 20-amp fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87.

• If greater than the specified range, replace the relay.




Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Relay Replacement (Attached to Wire Harness) (Relay Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (Relay Replacement (Within an Electrical Center))
* Liftgate Outside Handle Replacement (Service and Repair)
* Liftgate Latch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup and programming


pro multis · About Operation CHARM