GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

DEFINITION: Door locks do not operate from the door lock cylinder switch, mounted on the exterior door key lock cylinder, of the driver or passenger door. This test assumes that all DTCs have been diagnosed.

1

Did you perform A Diagnostic System Check - Door Systems?

Go to Step 2

Go to Diagnostic System Check - Door Systems

2

  1. Install a scan tool.
  2. Turn ON the ignition, leaving the engine OFF.
  3. Observe the Driver (Pass.) Door Cylinder Sw. parameter in the Driver Door Module Inputs data list using the scan tool.
  4. Activate the driver (passenger) door cylinder switch.
  5. Observe the Driver (Pass.) Door Cylinder Sw. parameter using the scan tool.

Does the Driver (Pass.) Door Cylinder Sw. parameter change state?

Go to Step 9

Go to Step 3

3

  1. Disconnect the inoperative door cylinder switch harness connector.
  2. Observe the Driver (Pass.) Door Cylinder Sw. parameter using the scan tool.

Does the Driver (Pass.) Door Cylinder Sw. parameter change state?

Go to Step 6

Go to Step 4

4

  1. Disconnect the inoperative door cylinder switch harness connector.
  2. Install a 3 Amp fused jumper between door cylinder switch circuits.
  3. Observe the Driver (Pass.) Door Cylinder Sw. parameter using the scan tool.

Does the Driver (Pass.) Door Cylinder Sw. parameter change state?

Go to Step 8

Go to Step 5

5

Test the door cylinder switch circuits for an open, short or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 7

6

Inspect for poor connections/terminal tension at the door cylinder switch harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

7

Inspect for poor connections/terminal tension at the driver door module (passenger door module) harness connector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

8

Replace the door lock cylinder. Refer to Door Lock Cylinder Replacement .

Did you complete the replacement?

Go to Step 10

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9

Replace the driver door module. Refer to Door Control Module Replacement - Front .

Did you complete the replacement?

Go to Step 10

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10

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2