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 B153F 02: Liftgate Object Sensor Signal Circuit Short to GroundDTC B153F 05: Liftgate Object Sensor Signal Circuit Short to Battery or 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 liftgate object sensor uses 2 tape switches embedded in the liftgate opening weatherstrip to detect any foreign objects in the path of the liftgate. When pressure is applied to the weatherstrip, the tape switch is closed signaling the power liftgate module (LGM) that an object is in the path of the liftgate. The LGM will reverse the direction of the liftgate motor should this occur.
The 2 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 LGM to perform diagnostic functions on the circuits. When both switches are open, voltage supplied by the LGM passes through the resistors and supplies the LGM with a reference voltage. If an object is in the path of the moving liftgate, the affected switch would close. The closing of the switch would bypass the resistor and change the reference voltage seen by the LGM, indicating that one of the switches is closed and an object has been detected. 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 B153F 02 will set when the LGM detects a short to ground in the liftgate tape switch signal circuit. |
| • | DTC B153F 05 will set when the LGM detects a short to voltage or an open/high resistance in the liftgate tape switch signal circuit. |
Action Taken When the DTC Sets
The LGM will suspended power liftgate operation until the conditions for setting the DTC are no longer present. If the liftgate is in motion prior to the DTC setting, it will reverse and liftgate operation will be suspended.
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
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 harness connectors at the left and right liftgate tape switches.
- Ignition OFF, test for less than 1 ohm of resistance between the low reference circuit terminal B and ground at the left liftgate tape switch harness connector.
- Ignition ON, test for 5 volts between the signal circuit terminal A and ground at the right liftgate tape switch harness connector.
- Ignition OFF, disconnect the C1 harness connector at the LGM.
- Ignition ON, verify that a test lamp does not illuminate between the signal circuit terminal A and ground.
- If all circuits test normal, test or replace the affected liftgate tape switch.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the LGM. |
| ⇒ | 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 LGM. |
| ⇒ | If the test lamp illuminates, test the signal circuit for a short to voltage. |
Component Testing
- Ignition OFF, disconnect the harness connector at the right liftgate tape switch.
- Test for 10K ohms of resistance between the signal terminal A and the low reference terminal B.
- Disconnect the harness connector at the left liftgate tape switch.
- Test for 10K ohms of resistance between the signal terminal A and the low reference terminal B.
| ⇒ | If not within the specified range, replace the right liftgate tape switch. |
| ⇒ | If not within the specified range, replace the left liftgate tape switch. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for LGM replacement, setup, and programming |
