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 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.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics (Door Lock/Indicator Schematics)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
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
1. Ignition ON, observe the scan tool Window Lockout Switch parameter while pressing the window lockout switch on the S79D driver door lock/window switch. The value should change from Inactive to Active each time the switch is pressed.
• If the value is always Inactive or always Active, replace the S79D driver door lock/window switch.
2. Command the doors to LOCK and UNLOCK with the scan tool, all doors should LOCK and UNLOCK while changing between the commanded states.
• If either rear door does not LOCK or UNLOCK, refer to Power Door Locks Malfunction (Power Door Locks Malfunction).
3. With all the doors locked, command the child security lockout by pressing the window lockout switch on the S79D driver door lock/window switch, the interior rear door handles should not open the doors when used.
• If both interior rear door handles continue to function, refer to Child Security Door Lockout Inoperative.
• If the left or right interior rear door handles continue to function, refer to Child Security Door Lockout Malfunction.
Circuit/System Testing
Child Security Door Lockout Inoperative
1. Ignition OFF, disconnect the X1 harness connector at the X50A fuse block-underhood.
2. Test for less than 30 ohm between the ground circuit terminal 71 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition OFF, connect the X1 harness connector and disconnect the X2 harness connector at the X50A fuse block-underhood
4. Connect a test lamp between the control circuit terminal 13 and ground.
5. Ignition ON, command the child security lockout by pressing the window lockout switch on the S79D driver door lock/window switch. The test lamp should turn ON and OFF when changing between the commanded states.
• 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 K9 BCM.
• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
6. If all circuits test normal, replace the X50A fuse block-underhood.
Child Security Door Lockout Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate A23R door latch assembly-rear.
2. Connect a test lamp between the control circuit terminals listed below:
* A23LR door latch assembly-left rear terminal 2 and terminal 9
* A23RR door latch assembly-right rear terminal 4 and terminal 7
3. Command the child security lockout by pressing the window lockout switch on the S79D driver door lock/window switch, the test lamp should briefly illuminate while changing between the commanded states.
• If the test lamp is always OFF, test either control circuit for an open/high resistance.
4. If all circuits test normal, test or replace the A23R door latch assembly-rear.
Component Testing
1. Ignition OFF, disconnect the harness connector at the appropriate A23R door latch assembly-rear.
2. Install a 25 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 A23R door latch assembly-rear should perform the LOCK and UNLOCK functions.
• If it does not perform as specified, replace the A23R door latch assembly-rear.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Rear Side Door Lock Replacement (Rear Side Door Lock Replacement)
* Fuse Block Replacement (Fuse Block Replacement)
* Front Side Door Window Switch Replacement (Front Side Door Window Switch Replacement)
* Control Module References (Programming and Relearning)for BCM replacement, setup and programming