Operation CHARM: Car repair manuals for everyone.

Power Door Child Lock Malfunction





Power Door Child Lock Malfunction

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.

Diagnostic Fault Information






Circuit/System Description

The child door lockout switch is on the driver door lock/window switch and controls the child locks on the rear doors as well as the rear window switches. When the body control module receives a command from the window lockout switch, it will apply voltage to the door dead lock 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.

The body control module monitors the voltage level of the rear lock status signal circuits to determine if the rear door latches have been locked out. A switch within the rear door latch will be open or closed depending upon the lockout status of the rear latch. If the rear latches are locked out, the switch will be open and the body control module will disable the functions of the rear window switches. If the latches have not been lockout, the switch will be closed, pulling the voltage within the signal circuit to 0 volts and the body control module will permit normal rear window switch functions.

Reference Information

Schematic Reference

Door Lock/Indicator Schematics Door Lock/Indicator Schematics

Connector End View Reference

Component Connector End Views Sunshade - Left

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 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 rear door handles open the rear doors
Refer to Circuit/System Testing - Security Lockout Inoperative.

If a single interior rear door handle opens the rear door
Refer to Circuit/System Testing - Single Door Security Lockout Malfunction.

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 rear door handles do not open the rear doors
Refer to Circuit/System Testing - Security Lockout Inoperative.

If a single interior rear door handle does not open the rear door
Refer to Circuit/System Testing - Single Door Security Lockout Malfunction.

If both interior door handles open the rear doors

4. Verify both rear window switches do not open the rear windows when commanding the Child Security Lock Motors ON with a scan tool.

If a rear window switch continues to function
Refer to Circuit/System Testing - Rear Window Lockout Inoperative.

If the rear window switch is inoperative

5. Verify the scan tool Child Security Lock/Window Lockout Switch parameter changes between On and Off when pressing the lockout switch on the S79D Window Switch - Driver.

If the parameter does not change
Replace the S79D Window Switch - Driver.

If the parameter changes

6. All OK.

Circuit/System Testing

Security Lockout Inoperative

1. Ignition OFF and all vehicle systems OFF, disconnect the X1 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 71 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 X1 harness connector at the X50A Fuse Block-Underhood. Disconnect the X5 harness connector at the K9 Body Control Module, ignition ON.

4. Verify that a test lamp does not illuminate between the control circuit terminal 16 and ground.

If the test lamp illuminates

1. Ignition OFF, 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 16 X5 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 16 and B+.

6. You should either hear or feel the KR114 Door Dead Lock Relay click as the relay activates.

If the KR114 Door Dead Lock 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 16 X5 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 KR114 Door Dead Lock Relay activates

7. Replace the K9 Body Control Module.

Single Door Security Lockout Malfunction

1. Ignition OFF, disconnect the harness connector at the appropriate A23 Door Latch Assembly-Rear. Ignition ON

2. Connect a test lamp between control circuit terminals listed below:

* A23LR Door Latch Assembly-Left Rear - control circuit terminal 4 and control circuit terminal 7

* A23RR Door Latch Assembly-Right Rear - control circuit terminal 2 and control circuit terminal 9

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 remains OFF during either of the commands

1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K9 Body Control Module.

2. Test for infinite resistance between each control circuit and ground.

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

If infinite resistance, replace the K9 Body Control Module.

If the test lamp turns ON during each of the commands

4. Test or replace the rear A23 Door Latch Assembly.

Rear Window Lockout Inoperative

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the appropriate A23 Door Latch Assembly-Rear. 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 listed below and ground:

* A23LR Door Latch Assembly-Left Rear - ground circuit terminal 8

* A23RR Door Latch Assembly-Right Rear - ground circuit terminal 3

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 ON.

4. Verify the scan tool Rear Child Security Lock Switch parameter is Inactive.

If not Inactive

1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.

2. Test for infinite resistance between the signal circuit terminal listed below and ground.

* A23LR Door Latch Assembly-Left Rear - signal circuit terminal 9

* A23RR Door Latch Assembly-Right Rear - signal circuit terminal 4

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

If infinite resistance, replace the K9 Body Control Module.

If Inactive

5. Install a 3 A fused jumper wire between the signal and the ground circuit terminals listed below:

* A23LR Door Latch Assembly-Left Rear - signal circuit terminal 9 and ground circuit terminal 8

* A23LR Door Latch Assembly-Left Rear - signal circuit terminal 4 and ground circuit terminal 3

6. Verify the scan tool Rear Child Security Lock Switch parameter is Active.

If not Active

1. Ignition OFF, remove the 3 A fused jumper wire, disconnect the harness connector at the K9 Body Control Module, ignition ON.

2. Test for less than 1 V between the signal circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.

If less than 1 V

3. Test for less than 2 ohms in the signal 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 Active

7. Test or replace the A23 Door Latch Assembly-Rear.

Component Testing

Door Latch Test

1. Ignition OFF, disconnect the harness connector at the appropriate A23 Door Latch Assembly-Rear.

2. Install a 30 A fused jumper wire between one of the control terminals and 12 V. Momentarily install a jumper wire between the other control terminal and ground. Reverse the jumper wires at least two times, the A23 Door Latch Assembly-Rear should perform the LOCK and UNLOCK functions.

If the function does not perform the LOCK and UNLOCK function
Replace the A23 Door Latch Assembly-Rear.

If the function performs the LOCK and UNLOCK function

3. All OK

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Rear Side Door Lock Replacement Rear Side Door Lock Replacement

* Front Compartment Fuse Block Replacement Front Compartment Fuse Block Replacement

* Front Side Door Window and Multifunction Switch Replacement (Drivers Side Door) Front Side Door Window and Multifunction Switch Replacement (Drivers Side Door)

* Control Module References Control Module References for Body Control Module replacement, programming and setup