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For 1990-2009 cars only
Makes 🢒 Buick 🢒 1998 🢒 LeSabre 🢒 Body and Accessories 🢒 Doors 🢒 Power Door Locks Inoperative - All Doors and Switches

Power Door Locks Inoperative - All Doors and Switches Without Keyless Entry

Step

Action

Value(s)

Yes

No

1

Did you perform the Power Door Locks System Check?

--

Go to Step 2

Go to Power Door Locks System Check

2
  1. Enter the body control module (MALL) diagnostic mode.
  2. Press and hold the power door unlock switch.
  3. Cycle the headlamps 6 times.
  4. Release the power door unlock switch.
  5. The MALL module may sound a few bongs (history codes) upon entering the diagnostic mode. Refer to Body Control Module Diagnostic Information in Body Control System.
  6. Press a front power door lock switch to the UNLOCK position, then to the LOCK position switch.
  7. Does the MALL module sound 1 bong for each press of the transmitter door lock or unlock switch?

--

Go to Step 4

Go to Step 3

3

Inspect the other functions controlled by the MALL, including the audible warnings and interior lamps.

Do some of the MALL module functions operate?

--

Go to Step 4

Go to Diagnostic System Check - Body Control System

4
  1. Use a digital multimeter (DMM) in order to backprobe the MALL module connector C1 between terminal A and terminal C.
  2. Press the front power door lock switch to LOCK.
  3. Press the front power door lock switch to UNLOCK.

Does the voltage measure within the specified range?

10-15 V

Go to Step 8

Go to Step 5

5

Inspect for poor terminal contact at the MALL module connector C1. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.

Is the terminal contact OK?

--

Go to Step 7

Go to Step 6

6

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

Is the repair complete?

--

Go to Power Door Locks System Check

--

7

Replace the MALL module. Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

--

Go to Power Door Locks System Check

--

8
  1. Use a DMM in order to backprobe any door lock actuator connector between terminal B and ground.
  2. Press the front power door lock switch to the LOCK position.

Does the voltage measure within the specified range?

10-15 V

Go to Step 10

Go to Step 9

9

Repair 1 of the following components:

    • Open in CKT 295 (GRY)
    • Poor terminal contact at the MALL module connector C1 terminal C. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Power Door Locks System Check

--

10

Repair 1 of the following components:

    • Open in CKT 294 (TAN)
    • Poor terminal contact at the MALL module connector C1 terminal A. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Power Door Locks System Check

--

Power Door Locks Inoperative - All Doors and Switches With Keyless Entry

Step

Action

Value(s)

Yes

No

1

Did you perform the Power Door Locks System Check?

--

Go to Step 2

Go to Power Door Locks System Check

2
  1. Enter the body control module (MALL) diagnostic mode.
  2. Press and hold the power door unlock switch.
  3. Cycle the headlamps 6 times.
  4. Release the power door unlock switch.
  5. The MALL module may sound a few bongs (history codes) upon entering the diagnostic mode. Refer to Body Control Module Diagnostic Information in Body Control System.
  6. Press a front power door lock switch to the UNLOCK position, then to the LOCK position switch.

Does the MALL module sound 1 bong for each press of the door lock and unlock switch?

--

Go to Step 4

Go to Step 3

3
  1. Use a digital multimeter (DMM) in order to backprobe the MALL module connector C1 between terminal A and terminal C.
  2. Press the front power door lock switch to LOCK.
  3. Press the front power door lock switch to UNLOCK.

Is the voltage within the specified range?

10-15 V

Go to Step 7

Go to Step 4

4

Inspect for poor terminal contact at the MALL module connector C1. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.

Is the terminal contact OK?

--

Go to Step 6

Go to Step 5

5

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

Is the repair complete?

--

Go to Power Door Locks System Check

--

6

Replace the MALL module. Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

--

Go to Power Door Locks System Check

--

7
  1. Use a DMM in order to backprobe any door lock actuator connector between terminal B and ground.
  2. Press the front power door lock switch to the LOCK position.

Is the voltage within the specified range?

10-15 V

Go to Step 9

Go to Step 8

8

Repair the open in CKT 295 (GRY). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Power Door Locks System Check

--

9

Repair the open in CKT 294 (TAN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Power Door Locks System Check

--