Power Door Latch System Malfunction
Power Door Latch System 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 system is designed so that when the operator approaches a locked vehicle with the keyless entry transmitter, the keyless entry control module will detect the keyless entry transmitter and when an exterior door handle is pulled the keyless entry control module will command all doors to unlock and the door to unlatch allowing the door to be pulled open.
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 Latch 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)
Circuit/System Verification
1. Ignition ON, observe the scan tool keyless entry control module Exterior Driver Door, Exterior Passenger Door, Exterior Left Rear Door and Exterior Right Rear Door Handle Switch parameters while pulling and releasing each exterior door handle. The parameter should change between Active and Inactive.
• If a value for a exterior door handle is always Active or Inactive, refer to Exterior Door Handle Malfunction.
2. Ignition OFF, with the doors closed and locked, approach the vehicle with the keyless entry transmitter and pull the exterior driver door handle. The driver door should unlock and unlatch allowing the driver door to be pulled open.
• If the driver door does not perform as specified, refer to Driver Door Latch Malfunction.
3. With the doors closed and locked, approach the vehicle with the keyless entry transmitter and pull the exterior passenger door handle or the exterior left rear door handle or the exterior right rear door handle. The appropriate door should unlock and unlatch allowing the door to be pulled open.
• If all the doors do not perform as specified, refer to Passenger and Rear Door Release Command Inoperative.
• If a single door does not perform as specified, refer to Passenger or Rear Door Latch Malfunction.
4. With the doors unlocked, verify that the door latches perform the LOCK function when pressing the lock button on the driver door handle.
• If the doors do not LOCK, refer to Door Handle Lock Switch Malfunction.
5. With the doors unlocked, verify that the door latches perform the LOCK function when pressing the lock button on the passenger door handle.
• If the doors do not LOCK, refer to Door Handle Lock Switch Malfunction.
Circuit/System Testing
Exterior Door Handle Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate B27 door handle switch.
2. Test for less than 30 ohm between the ground circuit terminal 1 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the appropriate scan tool Exterior Door Handle Switch parameter is Inactive.
• If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K48 keyless entry control module.
4. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 1. Verify the scan tool Exterior Door Handle Switch parameter is Active.
• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K48 keyless entry control module
5. If all circuits test normal, test or replace the B27 door handle switch.
Driver Door Latch Malfunction
1. Ignition OFF, disconnect the X4 harness connector at the K48 keyless entry control module.
2. Connect a test lamp between the signal circuit terminal 3 and ground.
3. Ignition ON, pull and release the exterior driver door handle. The test lamp should turn ON and OFF as the exterior driver door handle is pulled and released.
• If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
• If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
4. Ignition OFF, connect the X4 harness connector at the K48 keyless entry control module and disconnect the harness connector at the A23D door latch assembly - driver.
5. Connect a test lamp between the control circuit terminal 5 and control circuit terminal 10
6. Ignition ON, pull and release the exterior driver door handle. The test lamp should briefly illuminate when pulling the exterior driver door handle.
• If the test lamp is always ON, test either control circuit for a short to voltage. If the circuit tests normal, replace the K48 keyless entry control module.
• If the test lamp is always OFF, test either control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K48 keyless entry control module.
7. If all circuits test normal, test or replace the A23D door latch assembly - driver.
Passenger or Rear Door Latch Malfunction
1. Ignition OFF, disconnect the X4 harness connector at the K48 keyless entry control module.
2. Connect a test lamp between the signal circuit terminal 14 and ground.
3. Ignition ON, pull and release the exterior door handle. The test lamp should turn ON and OFF as the exterior driver door handle is pulled and released.
• If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
• If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
4. Ignition OFF, connect the X4 harness connector at the K48 keyless entry control module and disconnect the harness connector at the appropriate A23 door latch assembly.
5. Connect a test lamp between the control circuit terminal 5 and control circuit terminal 10.
6. Ignition ON, pull and release the exterior door handle. The test lamp should briefly illuminate when pulling the exterior door handle.
• If the test lamp is always ON, test either control circuit for a short to voltage. If the circuit tests normal, replace the K48 keyless entry control module.
• If the test lamp does not illuminate, test either control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K48 keyless entry control module.
7. If all circuits test normal, test or replace the A23 door latch assembly.
Front Door Handle Lock Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate B27 door handle switch.
2. Test for less than 5 ohm between the ground circuit terminal 4 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Exterior Door Handle Proximity Sensor parameter is Inactive.
• If not the specified value, test the signal circuit terminal 3 for a short to ground. If the circuit tests normal, replace the K48 keyless entry control module.
4. Connect a 3 A fused jumper wire between the signal circuit terminal 3 and ground, verify the scan tool Exterior Door Handle Proximity Sensor parameter is Active.
• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K48 keyless entry control module.
5. If all circuits test normal, test or replace the B27 door handle switch.
Component Testing
Exterior Door Handle Switch Test
1. Ignition OFF, disconnect the harness connector at the appropriate B27 door handle switch.
2. With the switch in the open position, test for infinite resistance between the signal terminal 2 and the ground terminal 1.
• If not the specified value, replace the B27 door handle switch.
3. With the switch in the closed position, test for less than 5 ohm between the signal terminal 2 and the ground terminal 1
• If greater than the specified range, replace the B27 door handle switch.
Door Latch
1. Ignition OFF, disconnect the harness connector at the appropriate A23 door latch assembly.
2. Install a 15 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 should perform the LOCK and UNLOCK functions.
• If it does not perform as specified, replace the A23 door latch assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Front Side Door Outside Handle Replacement (Base) (Service and Repair)Front Side Door Outside Handle Replacement (ATH) (Service and Repair)
* Rear Side Door Lock Replacement (Rear Side Door Lock Replacement)
* Front Side Door Lock Replacement (Front Side Door Lock Replacement)
* Rear Side Door Outside Handle Replacement (Rear Side Door Outside Handle Replacement)
* Control Module References (Programming and Relearning)for BCM and the keyless entry control module replacement, setup, and programming