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Liftgate/Liftgate Window Ajar Indicator Malfunction



Liftgate/Liftgate Window Ajar Indicator Malfunction

Diagnostic Instructions

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

Diagnostic Fault Information





Circuit/System Description

The REAR ACCESS OPEN message displays and Gate Ajar indicator comes on if the liftgate or liftglass is open while the ignition is in RUN. The IPC receives a class 2 message from the liftgate module (LGM) requesting illumination. The LGM receives discrete inputs from 2 ajar switches to indicate the status of the liftgate. The liftgate and liftglass ajar switches are normally open when the liftgate and liftglass are closed. When the liftgate or liftglass is opened, the ajar switch contacts close providing a path to ground.

Reference Information
Schematic Reference

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

Component Connector End Views (Component Connector End Views)
Description and Operation

Door Ajar Indicator Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Control Module References) for scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool Liftglass Ajar Switch parameter while opening and closing the liftgate window. The reading should change between Closed and Ajar.

If the reading does not change between the specified values, refer to Liftglass Ajar Switch Circuit Test.

2. Observe the scan tool Liftgate Ajar Switch parameter while opening and closing the liftgate. The reading should change between Closed and Ajar.

If the reading does not change between the specified values, refer to Liftgate Ajar Switch Circuit Test.

3. If the liftgate and liftglass ajar switch inputs to the LGM function normally replace the IPC.

Circuit/System Testing

Liftglass Ajar Switch Circuit Test
1. Ignition OFF, disconnect the harness connector at the liftglass ajar switch.
2. Test for less than 5.0 ohms between the low reference circuit terminal B and ground.

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

3. Ignition ON, verify the scan tool Liftglass Ajar Switch parameter is Closed.

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

4. Install a 3A fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B. Verify the scan tool Liftglass Ajar Switch parameter is Ajar.

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.

5. If all circuits test normal, test or replace the liftglass ajar switch.

Liftgate Ajar Switch Circuit Test
1. Ignition OFF, disconnect the X1 harness connector at the liftgate latch.
2. Test for less than 5.0 ohms between the low reference circuit terminal D and ground.

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

3. Ignition ON, verify the scan tool Liftgate Ajar Switch parameter is Closed.

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

4. Install a 3A fused jumper wire between the signal circuit terminal B and the low reference circuit terminal D. Verify the scan tool Liftgate Ajar Switch parameter is Ajar.

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.

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

Repair Instructions

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

* Liftgate Window Latch Replacement (Service and Repair)
* Control Module References (Control Module References) for LGM or IPC replacement, programming, and setup