Liftgate Ajar Indicator Malfunction (RPO TB7)
Liftgate Ajar Indicator Malfunction (RPO TB7)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (with HP2) (Initial Inspection and Diagnostic Overview)Diagnostic System Check - Vehicle (without HP2) (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 body control module (BCM) receives an input from the liftgate ajar switch. The ajar switch is normally open when the liftgate is fully closed. When the liftgate is opened, the ajar switch contacts close providing a path to ground. The driver information center (DIC) located at the bottom of the instrument panel cluster (IPC), illuminates the REAR ACCESS OPEN message when the liftgate is open. The IPC receives a serial data message from the BCM indicating the liftgate ajar status.
Reference Information
Schematic Reference
Release Systems Schematics (Release Systems Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Door Ajar Indicator Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
Ignition ON, observe the scan tool Rear Closure Ajar Sw. parameter and the DIC display while opening and closing the liftgate. The parameter should change from Inactive to Active and the REAR ACCESS OPEN message should turn ON and OFF.
If the parameter changes from Inactive to Active but the DIC REAR ACCESS OPEN display is always ON or always OFF, replace the IPC.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the liftgate latch assembly.
2. Test for less than 1 ohm between the ground circuit terminal 5 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Rear Closure Ajar Sw parameter Inactive.
• If not the specified value, test the signal circuit terminal 6 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 6 and ground. Verify the scan tool Rear Closure Ajar Sw parameter is Active.
• 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 BCM.
5. If all circuits test normal, test or replace the liftgate latch assembly.
Component Testing
1. Ignition OFF, disconnect the harness connector at the liftgate latch assembly.
2. Test for infinite resistance between the signal terminal 6 and the ground terminal 5 with the switch in the open position.
• If not the specified value, replace the liftgate latch assembly.
3. Test for less than 2 ohms between the signal terminal 6 and the ground terminal 5 with the switch in the closed position.
• If greater than the specified range, replace the liftgate latch assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
Control Module References (Programming and Relearning) for BCM or IPC replacement, setup and programming