Power Door Locks Inoperative - Key Cylinder Switches

WARNING: This page is about a different car, the 2005 Buick LaCrosse and 2005 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.

Step	Action	Yes	No
Schematic Reference: Door Lock/Indicator Schematics Connector End View Reference: Power Door Systems Connector End Views DEFINITION: The key cylinder Lock/Unlock function is inoperative.
1	Did you perform the Diagnostic System Check - Vehicle?	Go to Step 2	Go to Diagnostic System Check - Vehicle
2	Verify that the power door locks key cylinder switches inoperative fault is present. Does the power door locks key cylinder switches system operate normally?	Go to Testing for Intermittent Conditions and Poor Connections	Go to Step 3
3	Does the power door locks system operate normally?	Go to Step 4	Go to Symptoms - Doors
4	Close all of the doors. Install a scan tool. With the scan tool, observe the appropriate Left Front (LF) or Right Front (RF) Key Cylinder Lock Switch parameter in the Data Display Inputs list of the body control module (BCM). Does the Key Cylinder Lock Switch parameter display the Idle state?	Go to Step 5	Go to Step 6
5	Insert the door key into the inoperative door lock cylinder switch. With the scan tool, observe the appropriate LF or RF Key Cylinder Lock Switch parameter in the Data Display Inputs list of the BCM. Turn the door key cylinder first to the LOCK position, and then to the UNLOCK position. Did the Key Cylinder LOCK Switch parameter change from the Idle state to the Lock and UNLOCK states as expected?	Go to Step 12	Go to Step 7
6	Disconnect the harness connector of the inoperative door lock cylinder switch. Does the Key Cylinder Lock Switch parameter display the Idle state?	Go to Step 11	Go to Step 9
7	Disconnect the harness connector of the inoperative door lock cylinder switch. Connect a 3-amp fused jumper wire between the appropriate key switch lock or unlock signal circuit of the harness connector and a ground. With the scan tool, observe the appropriate Key Cylinder Lock Switch parameter. Did the Key Cylinder Lock Switch parameter display the appropriate state?	Go to Step 8	Go to Step 10
8	Connect the 3-amp fused jumper wire between the inoperative key switch lock or unlock signal circuit and the ground circuit of the harness connector. With the scan tool, observe the inoperative Key Cylinder Lock Switch parameter. Did the Key Cylinder Lock Switch parameter display the appropriate state?	Go to Step 11	Go to Step 13
9	Test the inoperative door lock cylinder switch signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?	Go to Step 16	Go to Step 12
10	Test the inoperative door lock cylinder switch signal circuit for an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?	Go to Step 16	Go to Step 12
11	Inspect for poor connections at the harness connector of the inoperative door lock cylinder switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?	Go to Step 16	Go to Step 14
12	Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?	Go to Step 16	Go to Step 15
13	Repair the open ground circuit of the door lock cylinder switch. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair?	Go to Step 16	-
14	Replace the inoperative door lock cylinder switch. Refer to Lock Cylinder Replacement - Door . Did you complete the replacement?	Go to Step 16	-
15	Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?	Go to Step 16	-
16	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 2