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 B153F 03: Liftgate Object Sensor Signal Circuit Voltage Below TresholdDTC B153F 07: Liftgate Object Sensor Signal Circuit Voltage Above Threshold
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 object sensor uses two 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 liftgate control module that an object is in the path of the liftgate. The liftgate control module 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 liftgate control module to perform diagnostic functions on the circuits. When both switches are open, voltage supplied by the liftgate control module passes through the resistors and supplies the liftgate control module with a reference voltage. If an object is in the path of the moving liftgate, the affected switch may close. The closing of the switch would bypass the resistor and change the reference voltage seen by the liftgate control module, indicating that one of the switches is closed and an object has been detected.
Conditions for Running the DTC
The system voltage is 9.5-16 V.
Conditions for Setting the DTC
B153F 03
When the liftgate control module detects less than 3.3 V in the liftgate tape switch signal circuit.
B153F 07
When the liftgate control module detects greater than 5.5 V in the liftgate tape switch signal circuit.
Action Taken When the DTC Sets
The power liftgate will be inoperative until the conditions for setting the DTC are no longer present. If the liftgate is in motion prior to the DTC setting, the liftgate will close and immediately re-open.
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. |
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
Connector End View Reference
Description and Operation
Rear Hatch/Gate Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Ignition ON, observe the scan tool Object Sensor Supply Voltage parameter while pressing and releasing the left and right liftgate object sensors. The parameter should change between Inactive and Active.
Circuit/System Testing
- Ignition OFF, disconnect the X1 harness connector at the K39 Liftgate Control Module.
- Test for infinite resistance between the signal circuit terminal M and ground.
- Test for 15 k -25 kΩ between the signal circuit terminal M and the low reference circuit terminal L.
- If all circuits test normal, replace the K39 Liftgate Control Module.
| ⇒ | If less than the specified value, test the signal circuit for a short to ground. |
| ⇒ | If not within the specified range, test the signal circuit between the B71L Liftgate Object Sensor - Left and B71R Liftgate Object Sensor - Right and the low reference circuit for an open/high resistance. If the circuits test normal, test or replace the B71L Liftgate Object Sensor - Left or B71R Liftgate Object Sensor - Right. |
Component Testing
- Ignition OFF, disconnect the harness connector at the B71R Liftgate Object Sensor - Right.
- Test for 10 kΩ between the signal terminal A and the low reference terminal B.
- Disconnect the harness connector at the B71L Liftgate Object Sensor - Left.
- Test for 10 kΩ between the signal terminal A and the low reference terminal B.
| ⇒ | If not within the specified value, replace the B71R Liftgate Object Sensor - Right. |
| ⇒ | If not within the specified value, replace the B71L Liftgate Object Sensor - Left. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Liftgate Object Sensor |
| • | Control Module References for liftgate control module replacement, setup and programming |
