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 B3125 00: Left Front/Driver Door Only Unlock CircuitDTC B3130 00: All Door Unlock Circuit
DTC B3135 00: All Door Lock Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
I/P Fuse Block B+ | 2 | 2 | -- | -- |
Driver Door Lock Switch Lock Signal | 1 | 1 | 1 | -- |
Driver Door Lock Switch Unlock Signal | 1 | 1 | 1 | -- |
Passenger Door Lock Switch Lock Signal | 1 | 1 | 1 | -- |
Passenger Door Lock Switch Unlock Signal | 1 | 1 | 1 | -- |
Door Unlock Relay Control | B3130 00 | B3130 00 | B3130 00 | -- |
Driver Door Relay Unlock Control | B3125 00 | B3125 00 | B3125 00 | -- |
Door Lock Relay Control | B3135 00 | B3135 00 | B3135 00 | -- |
Door Lock Switch Ground | -- | 1 | 1 | -- |
I/P Fuse Block Ground | -- | 2 | 2 | -- |
1. Door Lock Switch Malfunction 2. Door Latch Malfunction | ||||
Circuit/System Description
The body control module (BCM), upon receipt of a lock switch lock signal, will switch the Door Lock Relay Control circuit to battery positive voltage. This will energize the LOCK relay. The remaining unlock relays receive voltage from the underhood fuse block, the BCM upon receipt of a unlock signal or driver door unlock signal will switch the appropriate unlock relay to ground. This will energize the appropriate unlock relay unlocking the appropriate doors.
Conditions for Running the DTC
The system voltage must be between 9-16 volts.
Conditions for Setting the DTC
B3125 00
The BCM detects a fault in the driver door unlock control circuit while commanding the DRIVER UNLOCK relay.
B3130 00
The BCM detects a fault in the door unlock control circuit while commanding the UNLOCK relay.
B3135 00
The BCM detects a fault in the door lock control circuit while commanding the LOCK relay.
Action Taken When the DTC Sets
The power door locks will malfunction
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. |
Reference Information
Schematic Reference
Door Lock/Indicator Schematics
Connector End View Reference
Description and Operation
Power Door Locks Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Ignition ON, command the driver door and passenger door lock actuators to LOCK and UNLOCK with the scan tool, the doors should perform the LOCK and UNLOCK functions.
Circuit/System Testing
- Ignition OFF, disconnect the X1 harness connector at the I/P fuse block.
- Connect a test lamp between control circuit terminal K4 and ground.
- Ignition ON, command the Lock Rear Doors ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- Connect a test lamp between control circuit terminal K6 and B+.
- Command the Driver Door Unlock ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- Connect a test lamp between the control circuit terminal K5 and B+.
- Command the Unlock Rear Doors ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- If all circuits test normal, replace the I/P fuse block.
| ⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM. |
| ⇒ | If the test lamp is always OFF, test the control 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 and 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 and open/high resistance. If the circuit tests normal, replace the BCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
