• | 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 |
---|---|---|---|---|
Driver Door Switch B+ | 1 | 1 | -- | -- |
Door Lock Relay B+ | 3,4 | 3,4 | -- | -- |
Door Unlock Relay B+ | 3,4 | 3,4 | -- | -- |
Passenger Door Switch B+ | 2 | 2 | -- | -- |
Driver Door Latch Control | 1 | 1 | 1 | -- |
Passenger Door Latch Control | 2 | 2 | 2 | -- |
Door Lock Relay Control | B3808 | B3808 | 3,4 | -- |
Door Unlock Relay Control | B3809 | B3809 | 3,4 | -- |
Liftgate Latch Control | 5 | 5 | 5 | -- |
Rear Door Latch Control | 3,4 | 3,4 | 3,4 | -- |
Door Lock Relay Ground | -- | 3,4 | 3,4 | -- |
Door Unlock Relay Ground | -- | 3,4 | 3,4 | -- |
1. Driver Door Latch Malfunction 2. Passenger Door Latch Malfunction 3. Rear Door Unlock Inoperative 4. Rear Door Lock Inoperative 5. Liftgate Latch Inoperative |
The rear door lock actuators are controlled by the body control module (BCM) through the LOCK and UNLOCK relays, and the relays are controlled by the BCM through low side drive control circuits.
Door Lock/Indicator Schematics
Power Door Locks Description and Operation
Control Module References for scan tool information
Ignition ON, command the Rear Door Lock/Unlock with a scan tool. The rear doors should preform the LOCK and UNLOCK functions.
⇒ | If greater than the specified range, test the ground circuit for a short to voltage or an open/high resistance. |
• | B+ circuit terminal 86 |
• | B+ circuit terminal 87 |
⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance |
⇒ | If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp continuously illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If greater than the specified range, test the ground circuit for a short to voltage or an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp continuously illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the UNLOCK relay. |
⇒ | If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the LOCK relay. |
⇒ | If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the UNLOCK relay. |
⇒ | If the test lamp continuously illuminates, test the control circuit for a short to voltage. If the circuit tests normal, test or replace the UNLOCK relay. |
⇒ | If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the LOCK relay. |
⇒ | If the test lamp continuously illuminates, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the LOCK relay. |
⇒ | If not within the specified range, replace the relay. |
• | 30 and 86 |
• | 30 and 87 |
• | 30 and 85 |
• | 85 and 87 |
⇒ | If less than the specified value, replace the relay. |
⇒ | If greater than the specified range, replace the relay. |
⇒ | If greater than specified range, replace the relay. |
⇒ | If the function does not perform as specified, replace the door latch. |
⇒ | If the function does not perform as specified, replace the door latch. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, setup, and programming |