Chevrolet Trax: DTC B3930: Child security lock motors

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 B3930 01

Child Security Lock Motors Circuit Short to Battery

DTC B3930 02

Child Security Lock Motors Circuit Short to Ground

DTC B3930 04

Child Security Lock Motors Circuit Open

Diagnostic Fault Information

Circuit/System Description

The body control module controls the child security lock relay when it receives a command to lockout the rear doors. The relay will apply voltage to both child security circuits at the rear door latches to disable the interior rear door handles.

Conditions for Running the DTC

When the Door Lock relay is being actively commanded by the body control module.

Conditions for Setting the DTC

B3930 01

The body control module detects a short to voltage or an open/high resistance in the door lock security relay control circuit.

The body control module detects a an open/high resistance in the underhood fuse block ground circuit.

The body control module detects a short to ground or an open/high resistance in the body control module B+ circuit.

B3930 02

The BCM detects a short to ground in the door lock security relay control circuit.

B3930 04

The body control module detects a short to voltage or an open/high resistance in the door lock security relay control circuit.

The body control module detects a an open/high resistance in the underhood fuse block ground circuit.

The body control module detects a short to ground or an open/high resistance in the body control module B+ circuit.

Action Taken When the DTC Sets

• The interior rear door handles will always be disabled or will not lockout depending upon the latch states when the fault occurred
• The body control module will command the lockout indicator to flash ON and OFF for 30 seconds when the lockout switch is pressed to indicate a fault in the system.

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 (Encore), Door Lock/Indicator Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Power Door Locks Description and Operation

Electrical Information Reference

• Testing for Intermittent Conditions and Poor Connections
• Circuit Testing
• Wiring Repairs
• Connector Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.
2. Verify both interior rear door handles do not open the rear doors when commanding the Child Security Lock Motors ON with a scan tool.

• If both interior door handles open the rear doors

Refer to Circuit/System Testing.

• If both interior door handles do not open the rear doors

3. Verify both interior rear door handles will open the rear doors when commanding the Child Security Lock Motors OFF with a scan tool.

• If both interior door handles do not open the rear doors

Refer to Circuit/System Testing

• If both interior door handles open the rear doors

4. All OK

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the X2 harness connector at the X50A Fuse Block- Underhood. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal C5 and ground.

• If 10 ohms or greater

1. Ignition OFF.
2. Test for less than 2 ohms in the ground circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, repair the open/high resistance in the ground connection.
• If less than 10 ohms

3. Ignition OFF, connect the X2 harness connector at the X50A Fuse Block-Underhood. Disconnect the X4 harness connector at the K9 Body Control Module, ignition ON.
4. Verify that a test lamp does not illuminate between the control circuit terminal 8 and ground.

• If the test lamp illuminates

1. Ignition OFF, remove the test lamp, disconnect the X2 harness connector at the X50A Fuse Block- Underhood.
2. Test for less than 1 V between the K9 Body Control Module control circuit terminal 8 X4 and ground.

• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the X50A Fuse Block-Underhood.
• If the test lamp is not illuminated

5. Connect a 3A fused jumper wire between the control circuit terminal 8 and B+.
6. Listen for an audible click from the X50A Fuse Block-Underhood as the KR113 Child Security Lock Disable Relay activates.

• If the KR113 Child Security Lock Disable Relay does not activate

1. Ignition OFF, remove the jumper wire, disconnect the X2 harness connector at the X50A Fuse Block-Underhood.
2. Test for infinite resistance between the K9 Body Control Module control circuit terminal 8 X4 and ground.

• If less than Infinite resistance, repair the short to ground on the circuit.
• If infinite resistance

3. Test for less than 2 ohms in the control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the X50A Fuse Block-Underhood.
• If the KR113 Child Security Lock Disable Relay activates

7. Replace the K9 Body Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Front Compartment Fuse Block Replacement
• Control Module References body control module replacement, programming and setup

SYMPTOMS - VEHICLE ACCESS

NOTE: The following steps must be completed before using the symptom tables.

1. Perform the Diagnostic System Check - Vehicle , before using the Symptom Tables in order to verify that all of the following are true:

• There are no DTCs set
• The control modules can communicate via the serial data link

2. Review the system operation in order to familiarize yourself with the system functions. Refer to the following systems description:

• Door Ajar Indicator Description and Operation
• Rear Hatch/Gate Description and Operation
• Power Door Locks Description and Operation

Visual/Physical Inspection

• Inspect for aftermarket devices which may affect the operation of the system. Refer to Checking Aftermarket Accessories .
• Inspect the easily accessible or visible system components for obvious damage or conditions which may cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

• Power Door Child Lock Malfunction
• Door Ajar Indicator Malfunction
• Power Door Locks Malfunction
• Liftgate Release Malfunction

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