B153F
Liftgate Object Sensor Malfunction - DTC B153F
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC B153F 02
- Liftgate Object Sensor Signal Circuit Short to Ground
DTC B153F 05
- Liftgate Object Sensor Signal Circuit Short to Battery or Open
Diagnostic Fault Information
Circuit/System Description
The liftgate object sensors are pressure sensitive touch tapes located on either side of the upper inside edge of the liftgate panel. The two tape switches are placed in series between the liftgate object sensor signal circuit and the liftgate object low reference circuit. Each object sensor has a resistor as well as a switch. The resistors enable the liftgate control module to perform diagnostic functions on the circuits. When both touch tape sensors are not pressed, the 5 volt reference voltage supplied by the liftgate control module passes through the resistors and the liftgate control module detects approximately 3.3 volts. Pressing a touch tape will cause the voltage to drop to approximately to 2.5 volts indicating an obstruction is present. If the liftgate is in the open position, the liftgate control module will prohibit liftgate movement. If the obstruction occurs during the power close function, the liftgate control module will command the liftgate to reverse direction.
Conditions for Running the DTC
The system voltage is 9-16 V.
Conditions for Setting the DTC
B153F 02
The liftgate control module detects a short to ground in the liftgate tape switch signal circuit for greater than 10 minutes.
B153F 05
The liftgate control module detects a short to voltage or an open/high resistance in the liftgate tape switch signal circuit or an open/high resistance in the low reference circuit for greater than 10 minutes.
Action Taken When the DTC Sets
The liftgate control module will prevent any movement of the liftgate while attempting to command the liftgate to power close.
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
* If the liftgate will not release from the closed position, refer to Opening the Liftgate Without Electrical Power Service and Repair 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.
* If the liftgate mode switch is in the Off position, the liftgate will only open and close manually. Before testing the liftgate for power open and power close functions, verify that the liftgate mode switch is in the 3/4 or MAX position.
Reference Information
Schematic Reference
Liftgate Schematics Liftgate Schematics
Connector End View Reference
Component Connector End Views Sunshade - Left Front
Description and Operation
Liftgate Description and Operation Liftgate
Electrical Information Reference
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Circuit Testing Circuit Testing
* Wiring Repairs Wiring Repairs
* Connector Repairs Connector Repairs
Scan Tool Reference
Control Module References Programming and Relearning for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify the scan tool Liftgate Secondary Obstacle Detection parameter is between 3V-3.5V.
• If not between 3V-3.5V
Refer to Circuit/System Testing.
• If between 3V-3.5V
3. Verify the scan tool Liftgate Secondary Obstacle Detection parameter is between 3V-3.5V and changes to 2.25-2.75V as the B71R liftgate object sensor - right is pressed.
• If not between 2.25-2.75V or does not change
Test or replace the B71R liftgate object sensor - right.
• If between 2.25-2.75V and changes
4. Verify the scan tool Liftgate Secondary Obstacle Detection parameter is between 3V-3.5V and changes to 2.25-2.75V as the B71L liftgate object sensor - left is pressed.
• If not between 2.25-2.75V or does not change
Test or replace the B71L liftgate object sensor - left.
• If between 2.25-2.75V and changes
5. All OK.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the B71L liftgate object sensor - left. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohms between the low reference circuit terminal B and ground.
• If 10 ohms or greater
1. Ignition OFF.
2. Test for less than 2 ohms in the low reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 10 ohms
3. Disconnect the harness connector at the B71R liftgate object sensor - right.
4. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal A and ground.
• If less than 4.8 V
1. Ignition OFF, disconnect the harness connector at the K39 liftgate control module.
2. Test for infinite resistance between the 5 V reference circuit and ground
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the 5 V reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K39 liftgate control module.
• If greater than 5.2 V
1. Ignition OFF, disconnect the harness connector at the K39 liftgate control module, Ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K39 liftgate control module.
• If between 4.8-5.2 V
5. Test or replace the B71 liftgate object sensors.
Component Testing
1. Ignition OFF, disconnect the harness connector at the B71 liftgate object sensor.
2. Test for 8k-12k ohms between the signal terminal A and the low reference circuit terminal B.
• If not between 8k-12k
Replace the B71 liftgate object sensor.
• If between 8k-12k ohms
3. All OK
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Liftgate Side Upper Sensor Replacement (Equinox) Service and RepairLiftgate Side Upper Sensor Replacement (Terrain) Service and Repair
* Control Module References Programming and Relearning for liftgate control module replacement, setup and programming