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 |
|---|---|---|---|---|
Liftgate Latch Assembly Lock Control | 1 | 1 | -- | -- |
Liftgate Latch Assembly Unlock Control | 1 | 1 | -- | -- |
1. Liftgate lock malfunction | ||||
Circuit/System Description
The liftgate module (LGM) is directly connected to the liftgate lock actuator through the lock actuator lock and unlock control circuits. Once a door lock or unlock request has been received, the module will supply battery voltage to one side of the actuator and ground the other causing the liftgate to lock or unlock.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics
Connector End View Reference
Description and Operation
Power Door Locks Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Ignition ON, command the liftgate to LOCK and UNLOCK with a scan tool. The liftgate should perform the LOCK and UNLOCK functions.
Circuit/System Testing
- Ignition OFF, disconnect the X2 harness connector at the liftgate latch assembly.
- Test for less than 5 ohms between the control circuit terminal A and ground.
- Test for less than 5 ohms between the control circuit terminal B and ground.
- Connect a test lamp between control circuit terminal A and control circuit terminal B.
- Ignition ON, command the liftgate to LOCK and UNLOCK with a scan tool. The test lamp should illuminate during the LOCK and UNLOCK command.
- If all circuits test normal, test or replace the liftgate latch assembly.
| ⇒ | 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. |
| ⇒ | 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. |
| ⇒ | If the test lamp remains OFF during either of the commands, test either control circuit for a short to ground. If the circuits test normal, replace the LGM. |
Component Testing
- Ignition OFF, disconnect the harness connector at the liftgate latch assembly.
- Install a 15A fused jumper wire between the control terminal A and 12 volts. Momentarily install a jumper wire between the control terminal B and ground. The liftgate latch assembly should perform the LOCK/UNLOCK function.
- Reverse the jumper wires. The liftgate latch assembly should perform the UNLOCK/LOCK function.
| ⇒ | If the function does not perform as specified, replace the liftgate latch assembly. |
| ⇒ | If the function does not perform as specified, replace the liftgate latch assembly. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for LGM replacement, programming, and setup
