• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Liftgate Module B+ | B153A 08, B396A 02 | B153A 08, B396A 02 | -- | -- |
Liftgate Module B+ | U0230 00 | U0230 00 | -- | -- |
Liftgate Position Sensor 5V Reference Voltage | B153E 02 | B153B 08 | 2 | B1019 00 |
Full Open Signal | B153E 08 | B153B 05 | 2 | -- |
Liftgate Disable Signal | 1, 2 | 1 | 1 | -- |
Liftgate Open Signal | 1 | 1 | 1 | -- |
Object Sensors Signal | B153F 02 | B153F 05 | B153F 05 | B153F 03, B153F 07 |
Open/Close Switches Signal | B2494 02 | 1, 2 | 1, 2 | -- |
Pawl Switch Signal | B153A 00 | B153A 08 | B153A 00 | B153A 08 |
Position Sensor Signal 1 | B153E 08 | B153E 08 | B153E 05 | -- |
Position Sensor Signal 2 | B153E 08 | B153A 08 | B153E 05 | B153E 08 |
Ratchet Switch Signal | B153A 00 | B153A 08 | B153A 00 | B153A 08 |
Sector Switch Signal | B153A 00 | B153A 00 | B153A 00 | B153A 08 |
Disengage Clutch Control | B396B 02 | B396B 04 | B396B 01 | -- |
Engage Clutch Control | B396B 02 | B396B 04 | B396B 01 | -- |
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 | B153E 08 |
Liftgate Motor Open Control | B396A 02 | B396A 04 | B396A 01 | B153E 08 |
Full Open Low Reference | -- | B153B 05 | 2 | -- |
Liftgate Switches Low Reference | -- | B153A 08 | 1 | B153E 08 |
Position Sensor Low Reference | -- | B0153E 08 | 2 | -- |
I/P Switch Ground | -- | 1 | 1 | -- |
Liftgate Control Module Ground | -- | U0230 00 | 2 | -- |
1. Liftgate Switch Malfunction 2. Liftgate Malfunction |
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 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.
The system voltage is 9-16 volts.
When the LGM detects a short to ground in the liftgate tape switch signal circuit.
When the LGM detects less than 3.3 volts in the liftgate tape switch signal circuit.
When the LGM detects a short to voltage or an open/high resistance in the liftgate tape switch signal circuit.
When the LGM detects greater than 5.5 volts in the liftgate tape switch signal circuit.
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.
• | 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. |
Important: Before testing can be performed the liftgate must be opened. Refer to Opening the Liftgate Without Electrical Power 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.
Vehicle Access Connector End Views
Rear Hatch/Gate Description and Operation
Ignition ON, observe the scan tool Object Sensor Supply Voltage parameter while pressing and depressing the appropriate liftgate object sensor. The parameter should change between Inactive and Active.
⇒ | 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 left and right liftgate object sensors and the low reference circuit for an open/high resistance. If the circuits test normal, test or replace the left or right liftgate object sensor. |
⇒ | If not within the specified range, replace the right liftgate object sensor. |
⇒ | If resistance is not within the specified range, replace the left liftgate object sensor. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for LGM replacement, setup, and programming |