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 B153E 08: Liftgate Position Sensor Signal Circuit Performance -- Signal Invalid

### 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 control module continuously monitors power liftgate operation and calculates its location and direction of travel using 2 Hall effect sensors that are part of the gear motor assembly. The Hall effect sensors are 5 V 3-wire sensors and are supplied with a 5 V power, ground and signal circuits from the liftgate control module. The Hall effect sensor signal circuits are referenced from voltage within the liftgate control module and pulsed low by the Hall effect sensors.

### Conditions for Running the DTC

The system voltage is 9.5-16 V.

### Conditions for Setting the DTC

The liftgate control module does not detect optical sensor pulses when the liftgate is in motion.

### Action Taken When the DTC Sets

The power liftgate system will be disabled.

### 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.

### 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 S45B Liftgate Control Switch - Interior. The liftgate should power close, cinch-in, and latch.

### Circuit/System Testing

1. Ignition OFF, disconnect the X3 harness connector at the K39 Liftgate Control Module.
2. Ignition OFF, test for less than 1 Ω between the low reference terminal D at the K39 Liftgate Control Module and ground.

⇒ | If not the specified range, replace the K39 Liftgate Control Module.

3. Ignition ON, test for 4.8-5.2 V between 5 V reference terminal A at the K39 Liftgate Control Module and ground.

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

4. Ignition ON, test for 4.8-5.2 V are between sensor 1 signal terminal B and low reference terminal D at the K39 Liftgate Control Module.

⇒ | If not within the specified range, replace the K39 Liftgate Control Module.

5. Test for 4.8-5.2 V between sensor 2 signal terminal C and low reference terminal D at the K39 Liftgate Control Module.

⇒ | If not within the specified range, replace the K39 Liftgate Control Module.

6. If all circuits test normal, test or replace the B164 Liftgate Position Sensor.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Liftgate Position Sensor Replacement

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