• | 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 |
---|---|---|---|---|
Relay Switch B+ | 1, 2 | 1, 2 | -- | -- |
Rear Closure Handle Switch Open Signal | 1 | 1 | 1 | -- |
Liftgate Latch Relay Supply Voltage | B3265 | B3265 | B3265 | -- |
Liftgate Latch Relay Coil Control | B3265 | B3265 | B3265 | -- |
Liftgate Switch Ground | -- | 1, 2 | 1, 2 | -- |
Liftgate Latch Ground | -- | 2 | 2 | -- |
1. Liftgate Release Switch Inoperative 2. Liftgate Release Inoperative |
The liftgate can be released by operating the liftgate release switch or pressing the liftgate release button on the key fob. The gear selector may be in any position, but vehicle must be stationary for the liftgate to release.
Pressing the liftgate switch closes a contact providing a ground for the rear closure handle switch open signal circuit. The BCM will detect the voltage drop and command voltage to be supplied to the liftgate latch relay supply voltage circuit thus energizing the liftgate relay which provides voltage to the liftgate latch releasing the liftgate.
Vehicle Access Connector End Views
Rear Hatch/Gate Description and Operation
⇒ | If the reading does not change as specified, refer to Liftgate Switch Malfunction. |
⇒ | If the reading does not change as specified, refer to Liftgate Release Malfunction. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp is always OFF and the batt 2 fuse is good, test the B+ circuit for an open/high resistance. If the circuit tests normal, replace the underhood fuse block. |
⇒ | If the test lamp is always OFF and the batt 2 fuse is open, test the B+ circuit for a short to ground, if the circuit tests normal, replace the I/P fuse block. |
⇒ | If the test lamp is always ON, test the voltage circuit for a short to voltage. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp is always OFF, test the voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the I/P fuse block |
⇒ | If the test lamp is always OFF and the l/gate circuit fuse is good, test the control circuit for an open/high resistance, if the circuit tests normal, test or replace the I/P fuse block. |
⇒ | If the test lamp is always OFF and the l/gate circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test or replace the liftgate latch. |
⇒ | If the actuator does not perform as specified, replace the liftgate latch. |
⇒ | If not the specified value, replace the liftgate switch. |
⇒ | If greater than the specified range, replace the liftgate switch. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, setup, and programming |