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B3130




DTC B3130 or B3135

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptors
DTC B3130 00
- All Door Unlock Circuit

DTC B3135 00
- All Door Lock Circuit

Diagnostic Fault Information





Circuit/System Description

The body control module (BCM) internally grounds the door lock relay control circuit for the rear door lock relay when it receives a serial data message from the driver door module (DDM), passenger door module (PDM). When the BCM grounds the door lock relay control circuit the rear door lock relay is energized and locks the rear doors.

Conditions for Running the DTC

The system voltage is 9-16 volts.

Conditions for Setting the DTC

B3130 00

The BCM detects a fault on the UNLOCK relay control circuit.

B3135 00

The BCM detects a short to ground on the LOCK relay control circuit.

Action Taken When the DTC Sets

The rear 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 (Door Lock/Indicator Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Power Door Locks Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, command the rear doors to LOCK and UNLOCK with a scan tool. The rear doors should perform the LOCK and UNLOCK functions.

If B3135 00 is set refer to Door Lock Malfunction

If B3130 00 is set, refer to Door Unlock Malfunction

Circuit/System Testing

Door Lock Malfunction
1. Ignition OFF, disconnect the LOCK relay.
2. Test for less than 15 ohms between the relay coil ground circuit terminal and ground.

If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the relay coil ground circuit terminal and the relay coil control circuit terminal.
4. Ignition ON, command the rear doors to LOCK with a scan tool. The test lamp should briefly illuminate when commanding the LOCK state.

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.

5. If the circuit tests normal, test or replace the LOCK relay.

Door Unlock Malfunction
1. Ignition OFF, disconnect the UNLOCK relay.
2. Ignition ON, verify that a test lamp illuminates between the relay coil B+ circuit terminal and ground.

If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

3. Connect a test lamp between the relay coil B+ circuit terminal and the relay coil control circuit terminal.
4. Command the rear doors to UNLOCK with a scan tool. The test lamp should briefly illuminate when commanding the UNLOCK state.

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.

5. If the circuit tests normal, test or replace the UNLOCK relay

Component Testing

1. Ignition OFF, disconnect the appropriate relay.
2. Test for 60 - 200 ohms between terminals 85 and 86.

If not within the specified range, replace the relay.

3. Test for infinite resistance between the following terminals:

* 30 and 86
* 30 and 87
* 30 and 85
* 85 and 87

If not the specified value, replace the relay.

4. Test for less than 2 ohms between terminals 30 and 87A.

If greater than the specified range, replace the relay.

5. Install a 3A fused jumper wire between relay terminal 85 and 12V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87.

If greater than the specified range, replace the relay.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Relay Replacement (Attached to Wire Harness) (Relay Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (Relay Replacement (Within an Electrical Center))
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming