GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

DEFINITION: This test determines the cause of the inoperative door lock or locks and assumes that all DTCs have been diagnosed.

1

Did you perform the Door Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Door Systems

2

  1. Disconnect inoperative door lock motor electrical connector.
  2. Connect a test lamp between the inoperative door lock harness connector terminals.
  3. Choose the suspect door lock in the Door Lock Test application of the Output Control application of the Special Functions in the Driver Door Module data list using the scan tool.
  4. Command the door lock to lock and unlock.

Does the test lamp flash once upon commanding LOCK and once upon commanding UNLOCK?

Go to Step 6

Go to Step 3

3

Test the door lock actuator circuits for opens, shorts, shorts to power and ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the concern?

Go to Step 8

Go to Step 4

4

Inspect for poor connection/terminal tension at the door module. 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 8

Go to Step 5

5

Replace the door module. Refer to Door Control Module Replacement .

Did you complete the replacement?

Go to Step 8

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6

Inspect for poor connection/terminal tension at the door lock motor. 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 8

Go to Step 7

7

Replace the inoperative door lock motor. Refer to Front Side Door Latch Replacement or Rear Side Door Latch Replacement .

Did you complete the replacement?

Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2