GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Power Door Lock System Check?

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Go to Step 2

Go to Power Door Locks System Check

2

  1. Connect a scan tool to the data link connector (DLC).
  2. Select the body control module (PZM) on the scan tool.
  3. Move the inoperative door lock switch from the LOCK to the UNLOCK position.

Does the PZM receive the power door lock switch input?

--

Go to Step 3

Go to Step 4

3

Replace the PZM. Refer to Body Control Module Replacement in Body Control Systems.

Did you complete the repair?

--

Go to Power Door Locks System Check

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4

  1. Disconnect the inoperative door lock switch connector.
  2. Test the resistance from the switch connector terminal B to ground.

Is the resistance within the specified range?

0-5 ohms

Go to Step 6

Go to Step 5

5

Repair the open in one of the following circuits:

    • CKT 151 (BLK/WHT)
    • CKT 51 (BLK/WHT)

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Power Door Locks System Check

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6

  1. On the DeVille model, momentarily connect a fused jumper between the power door lock switch connector terminal B and terminal D, then terminal B and terminal A (front door only).
  2. On the Eldorado model, momentarily connect a fused jumper between the power door lock switch connector terminal B and terminal C, then terminal B and terminal A (front door only).

Do the door locks lock, then unlock?

--

Go to Step 8

Go to Step 7

7

Repair the open in one of the following circuits:

    • CKT 780 (RED/BLK)
    • CKT 781 (ORN/BLK)
    • CKT 245 (DK BLU)
    • CKT 244 (LT BLU)

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Power Door Locks System Check

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8

Inspect the power door lock switch connector for poor terminal connection.

Is the switch OK?

--

Go to Step 10

Go to Step 9

9

Repair the terminal contact. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Power Door Locks System Check

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10

Replace the door lock switch. Refer to Door Lock Switch Replacement .

Did you complete the repair?

--

Go to Power Door Locks System Check

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