Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

The liftgate module (LGM) controls operation of the liftgate latch motor and the liftgate actuator assembly. Under normal conditions the power latch can only be unlatched under power from the LGM through an input from the liftgate handle switch or the remote keyless entry (RKE) transmitter, but the liftgate may be manually closed to the primary latched position without the LGM performing the power latch function. The liftgate actuator assembly consists of the actuator drive motor with 2 internal Hall effect sensors. The drive motor is mated to a worm type gear off the actuator clutch and when the clutch is engaged the motor rotation is transferred to the clutch gear, intermediate gear, and actuator arm gear. The full open switch is a limit switch mounted on the liftgate actuator assembly along side the actuator arm gear, and will make contact with the cam on the actuator arm gear when the liftgate is near the full open position. The LGM continuously monitors the liftgate location and direction of travel using the 2 Hall effect sensors in the drive motor. The sensor counts are used to determine when the liftgate has reached the open and closed points of travel where the actuator clutch should be disengaged. These positions may vary slightly and must be learned when most liftgate components are serviced.

Power liftgate function will only be allowed if certain operating criteria are met. Any of the following may cause the power liftgate not to function:

The LGM also receives input from 2 pressure sensing object detection sensors. If either of these sensors indicates an object may be pinched as the liftgate is brought to the closed position, the liftgate will reverse direction and power close operation will be suspended until the pressure against the sensor is released.

Whenever the LGM loses power or is disconnected, the ignition must be cycled OFF then ON in order to reactivate the LGM.

Certain SIR DTC's will make the power liftgate inoperative. Correct any SIR concern first before performing any extensive power liftgate diagnostics.

Schematic Reference

Body Rear End Schematics

Connector End View Reference

Body Rear End Connector End Views

Electrical Information Reference

Scan Tool Reference

1. Ignition ON, observe the Liftgate Handle Sw. Status parameter while pressing and releasing the touchpad on the liftgate handle and the liftgate button next to the liftgate latch, the parameter should change from Inactive and Active.

⇒	If the parameter does not change, refer to Liftgate Handle Switch Inoperative.

2. Manually close the liftgate. The liftgate should close manually, cinch-in and latch.

⇒	If the liftgate fails to cinch-in or latch, refer to Latch Assembly Malfunction.

3. Open the liftgate and verify that the liftgate will remain at or near the full open position for several minutes.

⇒	If the liftgate will not remain open, replace the liftgate struts.

4. Command the liftgate to OPEN and CLOSE with a scan tool. The liftgate should OPEN and CLOSE as commanded.

⇒	If the liftgate fails to OPEN, refer to Power Liftgate Inoperative.

⇒	If the liftgate closes and immediately reopens, refer to Liftgate Closes and Reopens.

Liftgate Handle Switch Inoperative

1. Ignition OFF, disconnect the harness connectors at the liftgate close switch and liftgate handle switch.
2. Ignition ON, verify the scan tool Liftgate Handle Sw. Status parameter is Inactive.

⇒	If not the specified value, test the signal circuit terminal listed below for a short to ground. If the circuit tests normal, replace the LGM.

•	Liftgate close switch signal circuit terminal B

•	Liftgate handle switch signal circuit terminal A

3. Install a 3A fused jumper wire between the signal circuit terminal listed below and ground. Verify the scan tool Liftgate Handle Sw. Status parameter is Active.

•	Liftgate close switch signal circuit terminal B

•	Liftgate handle switch signal circuit terminal A

⇒	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.

4. Ignition OFF, connect the harness connector at the liftgate handle switch.
5. Ignition ON, observe the scan tool Liftgate Handle Sw. Status parameter while pressing and releasing the liftgate handle switch. The parameter should change between Active and Inactive.

⇒	If the parameter does not change, test or replace the liftgate handle switch.

6. If all circuits test normal, test or replace the liftgate close switch.

Latch Assembly Malfunction

1. Ignition OFF, disconnect the harness connector at the liftgate latch.
2. Test for less than 1 ohm between the control circuit terminal 1 and ground.

⇒	If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the LGM.

3. Test for less than 1 ohm between the control circuit terminal 3 and ground.

⇒	If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the LGM.

4. Ignition ON, connect a test lamp between the control circuit terminal 1 and control circuit terminal 3.
5. Command the liftgate to OPEN and CLOSE with a scan tool. The test lamp should illuminate when commanding the OPEN and CLOSE states.

⇒	If the test lamp does not illuminate during either of the commands, test either control circuit for a short to ground. If the circuits test normal, replace the LGM.

6. Ignition OFF, test for less than 1 ohm between the low reference circuit terminal 2 and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the LGM.

7. Ignition ON, verify the scan tool LGM Latch Pawl Sw. parameter is Inactive.

⇒	If not the specified parameter, test the signal circuit terminal 5 for a short to ground. If the circuit tests normal, replace the LGM.

8. Verify the scan tool LGM Latch Ratchet Sw. parameter is Inactive.

⇒	If not the specified parameter, test the signal circuit terminal 6 for a short to ground. If the circuit tests normal, replace the LGM.

9. Verify the scan tool LGM Latch Sector Sw. parameter is Inactive.

⇒	If not the specified parameter, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the LGM.

10. Install a 3A fused jumper wire between the signal circuit terminal 5 and low reference circuit terminal 2. Verify the scan tool LGM Latch Pawl Sw. parameter is Active.

⇒	If not the specified parameter, test the signal circuit terminal 5 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the LGM.

11. Install a 3A fused jumper wire between the signal circuit terminal 6 and low reference circuit terminal 2. Verify the scan tool LGM Latch Ratchet Sw. parameter is Active.

⇒	If not the specified parameter, test the signal circuit terminal 6 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the LGM.

12. Install a 3A fused jumper wire between the signal circuit terminal 4 and low reference circuit terminal 2. Verify the scan tool LGM Latch Sector Sw. parameter is Active.

⇒	If not the specified parameter, test the signal circuit terminal 4 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the LGM.

13. If all circuits test normal, test or replace the liftgate latch.

Power Liftgate Inoperative

1. Ignition OFF, disconnect the C2 harness connector at the LGM.
2. Test for less than 1 ohm between the ground terminal 6 and ground.

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

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 3 and ground.

⇒	If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the POWER LIFTGATE fuse is open, replace the LGM.

4. Verify that a test lamp illuminates between the B+ circuit terminal 4 and ground.

⇒	If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the REAR HATCH fuse is open, replace the LGM.

Liftgate Closes and Reopens

Important: Check the alignment of the liftgate striker, if the liftgate striker is adjusted too far inboard it could allow the LGM to detect an excess motor current condition and reverse the motor.

1. Ignition OFF, disconnect the C1 harness connector at the LGM.
2. Test for infinite resistance between the signal circuit terminal 8 and ground.

⇒	If less than the specified value, test the signal circuit for a short to ground.

3. Test for 15k-25k ohms between the signal circuit terminal 8 and the low reference circuit terminal 16.

⇒	If not within the specified range, test the signal circuit between the left and right liftgate object sensors and the low reference circuit for an open/high resistance. If the circuits test normal, test or replace the left or right liftgate object sensor.

4. If all circuits test normal, replace the LGM.

Liftgate Handle Switch

1. Ignition OFF, disconnect the harness connector at the liftgate handle switch.
2. Test for infinite resistance between the signal terminal A and the low reference terminal B with the switch in the open position.

⇒	If less than infinite resistance, replace the liftgate handle switch.

3. Test for less than 1 ohm between the signal terminal A and the low reference terminal B with the switch in the closed position.

⇒	If greater than 1 ohm, replace the liftgate handle switch.

Liftgate Close Switch

1. Ignition OFF, disconnect the harness connector at the liftgate handle switch.
2. Test for infinite resistance between the signal terminal B and the low reference terminal A with the switch in the open position.

⇒	If less than infinite resistance, replace the liftgate close switch.

3. Test for less than 1 ohm between the signal terminal B and the low reference terminal A with the switch in the closed position.

⇒	If greater than 1 ohm, replace the liftgate close switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.