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 03
- Liftgate Object Sensor Signal Circuit Voltage Below Treshold
DTC B153F 05
- Liftgate Object Sensor Signal Circuit Short to Battery or Open
DTC B153F 07
- Liftgate Object Sensor Signal Circuit Voltage Above Threshold
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 module to perform diagnostic functions on the circuits. When both touch tape sensors are not pressed, the 5 V reference voltage supplied by the liftgate module passes through the resistors and the liftgate module detects approximately 3.3 V. Pressing a touch tape will cause the voltage to drop to approximately to 2.5 V indicating an obstruction is present. If the liftgate is in the open position, the liftgate module will prohibit liftgate movement. If the obstruction occurs during the power close function, the liftgate 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 module detects a short to ground in the liftgate tape switch signal circuit.
B153F 03
The liftgate module detects less than 3.3 V in the liftgate tape switch signal circuit.
B153F 05
The liftgate module detects a short to voltage or an open/high resistance in the liftgate tape switch signal circuit.
B153F 07
The liftgate module detects greater than 5.5 V in the liftgate tape switch signal circuit.
Action Taken When the DTC Sets
The liftgate 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
Note: Before testing can be performed the liftgate must be opened. Refer to Opening the Liftgate Without Electrical Power Service and Repair for the appropriate procedure.
Whenever the LGM loses power or is disconnected, the ignition must be cycled OFF then ON in order to reactivate the LGM.
Reference Information
Schematic Reference
Liftgate Schematics Liftgate Schematics
Connector End View Reference
Component Connector End Views A/C Compressor Clutch
Description and Operation
Rear Hatch/Gate Description and Operation Rear Hatch/Gate
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON, observe the scan tool Object Detection Sensor Status parameter. The reading should be between 3-3.5 V.
• If not within the specified range, perform the Circuit/System Testing.
2. Observe the scan tool Object Sensor Supply Voltage parameter while pressing and releasing the B71R liftgate object sensor - right. The reading should change from Inactive to Active as the sensor is pressed and released.
• If the value does not change, test or replace the B71R liftgate object sensor - right.
3. Observe the scan tool Object Sensor Supply Voltage parameter while pressing and releasing the B71L liftgate object sensor - left. The reading should change from Inactive to Active as the sensor is pressed and released.
• If the value does not change, test or replace the B71L liftgate object sensor - left.
4. Command the liftgate to power close by pressing the B70 liftgate close switch and as the liftgate is closing, press the B71R liftgate object sensor - right or the B71L liftgate object sensor - left. The liftgate should stop and power open.
• If the liftgate continues to power close, replace the K39 liftgate module.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the B71L liftgate object sensor - left.
2. Test for less than 10 ohms between the low reference circuit terminal A and ground.
• If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K39 liftgate module.
3. Disconnect the harness connector at the B71R liftgate object sensor - right.
4. Ignition ON, test for 4.75-5.25 V between the signal circuit terminal B and ground.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K39 liftgate module.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K39 liftgate module.
5. Test of infinite resistance between the signal circuit terminal A and ground.
• If not the specified value, test the signal circuit for a short to ground.
6. Test for less than 10 ohms between the signal circuit terminal A at the B71R liftgate object sensor - right and the signal circuit terminal B at the B71L liftgate object sensor - left.
• If greater than the specified range, test the signal circuit for an open/high resistance.
7. If all circuits test normal, test or replace the appropriate B71 liftgate object sensor.
Component Testing
1. Ignition OFF, disconnect the harness connector at the appropriate B71 liftgate object sensor.
2. Test for 8k-12k ohms between the signal terminal A and the low reference terminal B.
• If not within the specified range, replace the B71 liftgate object sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Liftgate Side Upper Sensor Replacement (Acadia, Enclave, Traverse) Service and Repair
* Control Module References Control Module References for LGM replacement, programming and setup