B3930
DTC B3930
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 Descriptor
DTC B3930 02
- Child Security Lock Motors Circuit Short to Ground
Diagnostic Fault Information
Circuit/System Description
The child door lockout switch is on the driver door lock/window switch and controls the function of the rear interior door handles as well as the function of the rear window switches. When the BCM receives a command from the window lockout switch, it will apply voltage to the door lock security relay coil, this will energize the relay and the contact within the relay will then direct the voltage to lock the left rear and right rear child locks and then isolate them from the normal door lock system to prevent the rear doors from being opened by using the interior rear door handles.
Conditions for Running the DTC
When the relay is being actively commanded by the BCM.
Conditions for Setting the DTC
The BCM detects a short to ground in the child security lock relay circuit.
Action Taken When the DTC Sets
* The interior rear door handles will always function or will always be disabled depending upon the state of the rear door latch when the fault occurred.
* The BCM will command the lockout indicator to flash ON and OFF when the lockout switch is pressed.
Conditions for Clearing the DTC
* This 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 Fuel Pump and Level Sensor Assembly
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 Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify the operation of 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 the operation of 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, disconnect the X2 harness connector at the X50A fuse block-underhood.
2. Connect a test lamp between the control circuit terminal 13 and ground, ignition ON.
3. Verify the test lamp turns ON and OFF when commanding the Child Security Lock Motors ON and OFF with a scan tool.
• If the test lamp is always OFF
1. Ignition OFF, disconnect the harness connector at the K9 body control module.
2. Test for infinite resistance between the control circuit 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 K9 body control module.
• If the test lamp is always ON
1. Ignition OFF, disconnect the harness connector at the K9 body control module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K9 body control module.
• If the test lamp turns ON and OFF
4. Replace the X50A fuse block-underhood.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Front Compartment Fuse Block Replacement Front Compartment Fuse Block Replacement
* Control Module References Control Module References for BCM replacement, programming and setup