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. |
DTC Descriptors
DTC B396A 01: Liftgate Motor Control Circuit Short to BatteryDTC B396A 02: Liftgate Motor Control Circuit Short to Ground
DTC B396A 04: Liftgate Motor Control Circuit Open
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Latch Pawl Switch Signal | B153A 08 | B153A 08 | 1 | -- |
Latch Ratchet Switch Signal | B153A 08 | B153A 08 | 1 | -- |
Latch Sector Switch Signal | B153A 08 | B153A 08 | 1 | -- |
Liftgate Ajar Switch Signal | B396F 06 | B396F 06 | B396F 0B | -- |
Liftgate Latch Motor Close Control | B2495 02 | B2495 04 | B2495 01 | -- |
Liftgate Latch Motor Open Control | B2495 02 | B2495 04 | B2495 01 | -- |
Liftgate Motor Close Control | B396A 02 | B396A 04 | B396A 01 | -- |
Liftgate Motor Disengage Control | B396B 02 | B396B 04 | B396B 01 | -- |
Liftgate Motor Engage Control | B396B 02 | B396B 04 | B396B 01 | -- |
Liftgate Motor Open Control | B396A 02 | B396A 04 | B396A 01 | -- |
Liftgate Position Sensor Reference Voltage | B153E 02 | B153E 05 | B153E 05 | -- |
Liftgate Position Sensor Signal 1 | B153E 08 | B153E 08 | B153E 08 | -- |
Liftgate Position Sensor Signal 2 | B153E 08 | B153E 08 | B153E 08 | -- |
Liftgate Tape Switch Signal | B153F 02 | B153F 05 | B153F 05 | -- |
Liftgate Full Open Switch Signal | B153B 02 | B153B 05 | B153B 05 | -- |
Open/Close Switch Signal | B2494 02 | 1 | 1 | -- |
Liftgate Full Open Switch Low Reference | -- | B153A 08 | -- | -- |
Liftgate Handle Switch Low Reference | -- | 1 | -- | -- |
Liftgate Position Sensor Low Reference | -- | 1 | -- | -- |
Liftgate Tape Switch Low Reference | -- | B153F 05 | -- | -- |
1. Power Liftgate Malfunction | ||||
Circuit/System Description
The power liftgate motor is a bi-directional motor that is controlled by the liftgate control module (LGM). The LGM controls the liftgate motor through the control circuits by suppling power and ground in the appropriate polarity. The direction the motor operates is determined by which of the control circuits is supplied power and which is grounded. The LGM varies the current flow through the motor ground circuit to control the speed of the motor as necessary. For more detailed information concerning power liftgate operation refer to Liftgate Description and Operation .
Conditions for Running the DTC
Battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
| • | DTC B396A 01 will set when the LGM detects a short to voltage in the liftgate motor open control circuit or the liftgate motor close control circuit. |
| • | DTC B396A 02 will set when the LGM detects a short to ground in the liftgate motor open control circuit or the liftgate motor close control circuit. |
| • | DTC B396A 04 will set when the LGM detects an open/high resistance in the liftgate motor open control circuit or the liftgate motor close control circuit. |
Actions Taken When the DTC Sets
| • | If the liftgate is in motion when the DTC sets, liftgate operation will be disabled and resort to manual operation. |
| • | If the liftgate is not in motion when the DTC sets, all liftgate functions will be disabled. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | You issue a scan tool CLEAR DTCs command. |
Diagnostic Aids
| • | In some cases, the LGM may interpret circuit faults as if the liftgate has encountered an object in its travel and reverse direction. |
| • | Whenever the LGM is disconnected or loses power, the ignition must be cycled OFF then ON. |
Reference Information
Schematic Reference
Connector End View Reference
Vehicle Access Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
- Ignition OFF, disconnect the C3 harness connectors at the LGM.
- Ignition OFF, test for less than 1 ohm of resistance between the control circuit terminal 1 and control circuit terminal 2.
- Ignition OFF, verify that continuity is not present between both motor control circuit terminals at the C3 harness connector and ground.
- If all circuits test normal, replace the LGM.
| ⇒ | If greater than the specified range, replace the liftgate motor assembly. |
| ⇒ | If continuity is present, replace the liftgate motor assembly. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for LGM replacement, setup, and programming |
