GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Definition: The BCM does not sound the headlamps-on reminder when the following conditions exist:

    • The driver door is open.
    • The headlamp switch is in either the PARK or the HEAD position.
    • The key is removed from the ignition switch.

1

Was the Body Control Module (BCM) System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - Body Control System

2

  1. Turn the instrument panel dimmer switch off.
  2. Turn the interior lamps override switch to the ON positon. theis enables the interior courtesy lamps.
  3. Turn the ignition switch to the RUN position.
  4. Lower the driver window in order to prevent lockout.
  5. Close all of the vehicle doors.
  6. While observing the courtesy lamps, open and then close the driver's door.

Did the courtesy lamps light with the driver door open?

--

Go to Step 3

Go to Step 6

3

  1. Close all of the vehicle doors.
  2. Turn the ignition switch from the RUN position to the LOCK position.
  3. While observing the courtesy lamps, remove the key from the ignition key cylinder.

Did the courtesy lamps turn on when removing the key from the ignition key cylinder?

--

Go to Step 4

Go to Step 7

4

  1. Turn the headlamp switch to the HEAD position.
  2. Using a J 39200 digital multimeter (DMM), measure the voltage between the BCM connector C2 terminal D5 and ground.

Is the voltage less than the specified value?

2 V

Go to Step 8

Go to Step 5

5

  1. Leave the J 39200 DMM connected from the previous step.
  2. Disconnect the electrical connector to the headlamp and IP lamp dimmer switch.
  3. Using the J 39200 DMM, measure the voltage.

Is the voltage less than the specified value?

2 V

Go to Step 9

Go to Step 10

6

The headlamp-on reminder is inoperative due to a malfunction between the BCM and the driver door-lock-ajar switch. Refer to Interior Lamps System Check in Lighting Systems.

Is the action complete?

--

Go to Step 11

--

7

The headlamp-on reminder is inoperative due to a malfunction between the BCM and the ignition key alarm switch. Refer to Key-in-Ignition Chime Always On .

Is the action complete?

--

Go to Step 11

--

8

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

Is the repair complete?

--

Go to Step 11

--

9

Replace the headlamp and IP lamp dimmer switch. Refer to Headlamp Switch Replacement in Lighting Systems.

Is the repair complete?

--

Go to Step 11

--

10

Repair the short to B+ in CKT 1872.

Is the repair complete?

--

Go to Step 11

--

11

  1. Turn the ignition switch to the LOCK position.
  2. Reinstall the connectors and the components that you removed.
  3. Turn the ignition switch to the RUN position for 6 seconds.
  4. Remove the BCM PRGRM fuse.
  5. Turn the ignition switch to the ACC position. The BCM sounds the chime several times equivalent to the BCM type which is installed on the vehicle.
  6. Within 1 second, turn the ignition switch from the ACC position to the LOCK position, then back to the ACC position. The BCM sounds any DTCs stored.

Are any BCM DTCs present?

--

Go to Diagnostic System Check - Body Control System

System OK