GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Power Door Locks System Check?

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Go to Step 2

Go to Power Door Locks System Check

2

  1. Enter the body control module (MALL) diagnostic mode.
  2. 1.1. Press and hold the power door unlock switch.
    1.2. Cycle the headlamps 6 times.
    1.3. Release the power door unlock switch.
  3. 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 Systems.
  4. Press a front power door lock switch to the UNLOCK position.

Does the MALL module sound 1 bong for each press of the switch?

--

Go to Step 3

Go to Step 5

3

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the MALL module connector C1.
  3. Use a Digital Multimeter (DMM) set to the ohms scale in order to measure CKT 294 (TAN) resistance from connector C1 terminal A to ground.

Is the resistance within the specified range?

0-5 ohms

Go to Step 4

Go to Step 10

4

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

Is the repair complete?

--

Go to Power Door Locks System Check

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5

  1. Disconnect the MALL module connector C2.
  2. Use a DMM set to the ohms scale in order to measure the resistance from the MALL module connector C2 terminal C6 to ground.
  3. Press the front power door lock switch to the UNLOCK position.

Is the resistance within the specified range?

0-5 ohms

Go to Step 6

Go to Step 8

6

Inspect the MALL module connector C2 for proper terminal contact at terminal C6. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.

Is the terminal contact OK?

--

Go to Step 10

Go to Step 7

7

Repair the terminal contact at the MALL module connector C2. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Power Door Locks System Check

--

8

Test for an open in CKT 781 (ORN/BLK) between the MALL module connector C2 terminal C6 and S252.

Is CKT 781 open?

--

Go to Step 9

Go to Step 10

9

Repair the open in CKT 781 (ORN/BLK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Power Door Locks System Check

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10

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

Is the repair complete?

--

Go to Power Door Locks System Check

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