For 1990-2009 cars

### 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 Descriptor

DTC B396A 01: Liftgate Motor Control Circuit Short to Battery
DTC 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
--- | --- | --- | --- | ---
Liftgate Position Sensor 5 V Reference Voltage | B153E 08 | 2 | 2 | --
Liftgate Disable Signal | 1, 2 | 1 | 1 | --
Liftgate Open Signal -- Exterior Switch | B396E 02 | 1 | 1 | --
Liftgate Open Signal -- Shut Face Switch | B396E 02 | 1 | 1 | --
Object Sensors Signal | B153F 02 | B153F 05 | B153F 05 | B153F 03, B153F 07
Liftgate Open Signal -- Exterior Switch | B396E 02 | 1 | 1 | --
Open/Close Switches Signal | B396D 02 | 1, 2 | 1, 2 | --
Pawl Switch Signal | B153A 08 | B153A 08 | B153A 08 | B153A 08
Position Sensor Signal 1 | B153E 08 | B153E 08 | B153E 08 | B153E 08
Position Sensor Signal 2 | B153E 08 | B153E 08 | B153E 08 | B153E 08
Ratchet Switch Signal | B153A 08 | B153A 08 | B153A 08 | B153A 08
Sector Switch Signal | B153A 08 | B153A 08 | B153A 08 | B153A 08
Liftgate Latch Cinch Control | B2495 02 | B2495 04 | B2495 01 | --
Liftgate Latch Release Control | B2495 02 | B2495 04 | B2495 01 | --
Liftgate Motor Close Control | B396A 02 | B396A 04 | B396A 01 | --
Liftgate Motor Open Control | B396A 02 | B396A 04 | B396A 01 | --
Liftgate Switches Low Reference | -- | B153A 08 | 1 | B153E 08
Position Sensor Low Reference | -- | B0153E 08 | 2 | --
Mode/Release Switch Ground | -- | 1 | 1 | --
Liftgate Control Module Ground | -- | U0230 00 | 2 | --
1. Liftgate Switch Malfunction 2. Liftgate Malfunction

### Circuit/System Description

The liftgate motor is a bi-directional motor and open or close operation is the result of the direction of the motor rotation. The liftgate control module controls the liftgate motor through the control circuits by supplying power and ground in the appropriate polarity. The motor control circuits are monitored by the liftgate control module prior to activation for a high or low condition and during motor operation for any irregular current flow conditions.

### Conditions for Running the DTC

• | The system voltage is 9.5-16 V.

• | Power open or close function is initiated.

### Conditions for Setting the DTC

#### B396A 01

The liftgate control module detects a short to voltage in the liftgate motor control circuits.

#### B396A 02

A loss of B+ voltage to the liftgate control module or the liftgate control module detects a short to ground in the liftgate motor control circuits.

#### B396A 04

The liftgate control module detects an open/high resistance in the liftgate motor control circuits.

### Action Taken When the DTC Sets

Power liftgate operation will be suspended.

### Conditions for Clearing the DTC

• | The DTC will be current for as long as the fault is present.

• | When the fault is no longer present, the DTC will be a history DTC.

• | A history DTC will clear after 50 ignition cycles.

### Diagnostic Aids

Note: Before testing can be performed the liftgate must be opened. Refer to Opening the Liftgate Without Electrical Power for the appropriate procedure.

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

In some circumstances high or low control circuit faults may cause the liftgate control module to react as if the liftgate has encountered an object in its travel and reverse direction.

### Reference Information

#### Schematic Reference

Liftgate Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Rear Hatch/Gate Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Ignition ON, doors unlocked, transmission in Park or Neutral, enable the power liftgate by pressing the liftgate enable/disable button on the S58B Rear Compartment Lid Release Switch - Interior
2. Open the liftgate by pressing the touchpad on the S58A Rear Compartment Lid Release Switch - Exterior. The liftgate should release and power open.
3. Close the liftgate by pressing the liftgate button switch. The liftgate should power close, cinch-in, and latch.

### Circuit/System Testing

1. Ignition OFF, disconnect the X2 harness connector at the K39 Liftgate Control Module.
2. Test for less than 1 Ω between the ground circuit terminal F 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 G 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 B+ circuit fuse is open, replace the K39 Liftgate Control Module.

4. Ignition OFF, connect the X2 harness connector and disconnect the X3 harness connector at the K39 Liftgate Control Module.
5. Test for less than 15 Ω between the control terminal G at the K39 Liftgate Control Module and ground.

⇒ | If greater than the specified range, replace the K39 Liftgate Control Module.

6. Test for less than 15 Ω between the control terminal H at the K39 Liftgate Control Module and ground.

⇒ | If greater than the specified range, replace the K39 Liftgate Control Module.

7. Install a 15 A fused jumper wire between the control circuit terminal G at the connector X3 and 12 V. Momentarily install a jumper wire between the control circuit terminal H at connector X3 and ground. The liftgate motor should perform the Open or Close function.

⇒ | If the function does not perform as specified, replace the M17 Liftgate Motor Assembly.

8. Install a 15 A fused jumper wire between the control circuit terminal H and 12 V. Momentarily install a jumper wire between the control circuit terminal G and ground. The liftgate motor should perform the Close or Open function.

⇒ | If the function does not perform as specified, replace the M17 Liftgate Motor Assembly.

9. If all circuits test normal, replace the K39 Liftgate Control Module.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Liftgate Close Actuator Motor Replacement

• | Control Module References for liftgate control module replacement, setup, and programming