GM Service Manual Online
For 1990-2009 cars only

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Action

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Schematic Reference: Door Lock/Indicator Schematics

DEFINITION: This diagnostic table should be used to diagnose a complete failure of all the unlock functions.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Actuate each door lock switch, one at a time, to the unlock position.

Did the doors unlock from each switch?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Did the doors unlock from any switch?

Go to Power Door Locks Inoperative - One Door or Switch

Go to Step 4

4

  1. Disconnect the door lock relay.
  2. Connect a test lamp between the door unlock control circuit at the door lock relay harness connector and a good ground.
  3. Actuate a door lock switch to the unlock position.

Does the test lamp illuminate?

Go to Step 5

Go to Step 7

5

Connect a test lamp between the door lock actuator unlock circuit at the door lock relay harness connector and B+.

Does the test lamp illuminate?

Go to Step 9

Go to Step 6

6

Inspect for poor connections at the door lock relay 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

Repair the open in the door unlock control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

--

8

Replace the door lock relay.

Did you complete the repair?

Go to Step 10

--

9

Repair the short to ground in the door lock actuator unlock circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2