GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Audible Warnings System Check?

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Go to Step 2

Go to Audible Warnings System Check

2

  1. Turn the ignition switch to the RUN position.
  2. Enter the body control module (MALL) diagnostic mode by completing the following procedure:
  3. 2.1. Press and hold the power unlock switch.
    2.2. Cycle the headlights 6 times.
    2.3. Release the power unlock switch.
  4. The mall module may sound a few tones upon entering diagnostic mode. The tones are the history DTC stored in the mall module. Refer to Body Control Module for a list of these DTCs.
  5. After the history DTC tones, the MALL goes into input/output mode.
  6. Turn ON the turn signals.

Does the chime sound when the turn signal is ON?

--

Go to Step 4

Go to Step 3

3

  1. Disconnect the MALL module connector C2.
  2. Measure the voltage from connector C2 terminal C12 (harness side) to ground.

Is the measured resistance more than the specified value when you turn ON the turn signal?

5 V

Go to Step 8

Go to Step 6

4

Inspect CKT 817 (DK GRN/WHT) for an open.

Is the circuit OK?

--

Go to Step 5

Go to Step 7

5

Perform the Vehicle Speed Input Test.

Is the test complete?

--

Go to Audible Warnings System Check

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6

Inspect CKT 16 (PPL) for an open.

Is the circuit OK?

--

Go to Exterior Lights Circuit Description

Go to Step 10

7

Repair the open in CKT 817 (DK GRN/WHT). Refer to Repairing Damaged Wire Insulation in Wiring Systems.

Is the repair complete?

--

Go to Audible Warnings System Check

--

8

Inspect the MALL module connector C2 for proper terminal contact.

Is the contact OK?

--

Go to Step 9

Go to Step 11

9

Replace the MALL module. Refer to Multifunction Alarm , Lock, and Lighting Module Replacement in Instrument Panel, Gauges and Console.

Is the replacement complete?

--

Go to Audible Warnings System Check

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10

Repair the open in CKT 16 (PPL). Refer to Repairing Damaged Wire Insulation in Wiring Systems.

Is the repair complete?

--

Go to Audible Warnings System Check

--

11

Reconnect MALL module connector C2 for proper connection contact.

Is the connection complete?

--

Go to Audible Warnings System Check

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