GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Door Lock/Indicator Schematics

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 in Wiring Systems

Go to Step 3

3

Does the power door locks system operate normally?

Go to Step 4

Go to Symptoms - Doors

4

  1. Turn OFF the ignition.
  2. Lock the doors.
  3. Disconnect the appropriate door lock cylinder switch.
  4. Connect a 3-amp fused jumper wire between the driver door lock switch unlock signal circuit of the appropriate door lock cylinder switch and the ground circuit of the appropriate door lock cylinder switch.

Did the doors unlock?

Go to Step 7

Go to Step 5

5

Test the driver door lock switch unlock signal circuit of the appropriate door lock cylinder switch for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 6

6

Test the ground circuit of the appropriate door lock cylinder switch for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 8

7

Inspect for poor connections at the harness connector of the appropriate door lock cylinder switch. 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 11

Go to Step 9

8

Inspect for poor connections at the harness connector of the body control module (BCM). 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 11

Go to Step 10

9

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

Did you complete the replacement?

Go to Step 11

--

10

Replace the BCM. Refer to Body Control Module Replacement .

Did you complete the replacement?

Go to Step 11

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11

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2