GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2001 🢒 Montana 🢒 Restraints 🢒 Seat Belts 🢒 DTC 002

Circuit Description

The Body Control Module (BCM) controls the inadvertent load battery rundown protection feature. The BCM de-energizes the courtesy lamps supply voltage circuit ten minutes after the ignition switch has been turned from the ACC position or the RUN position to the LOCK position or the OFF position.

The BCM restores power to the courtesy lamps supply voltage circuit when the following actions occur:

    • The ignition switch is turned from the LOCK position or the OFF position to the ACC position or the RUN position.
    • The key is removed from the ignition.
    • Any vehicle door is opened.
    • The dimmer switch is turned to the DOME position.
    • Any interior courtesy light connected to the courtesy lamps supply voltage circuit is turned on.
    • The BCM receives a message to unlock the doors from the Remote Control Door Lock Receiver (BCM type 3 or type 4 only).
    • A door is unlocked using a key (BCM type 4 only).

The inadvertent load battery rundown protection feature is mileage-sensitive. Vehicles with less than 15 total driven miles have a time-out of 162-198 seconds instead of 10 minutes.

Conditions for Setting the DTC

The BCM detects a short to battery voltage or ground in the courtesy lamps supply voltage circuit.

Action Taken When the DTC Sets
    • The BCM sets the Diagnostic Trouble Code (DTC) 2.
    • The inadvertent load battery rundown protection feature is disabled when the courtesy lamps supply voltage circuit is shorted to battery voltage.
    • The interior courtesy lights do not turn on when the courtesy lamps supply voltage circuit is shorted to ground.

Conditions for Clearing the MIL/DTC
    • A short to battery voltage or ground in the courtesy lamps supply voltage circuit is no longer present.
    • After you complete the repairs, refer to On-Board Diagnostic Features in order to clear the DTC.

Diagnostic Aids
    • If the problem is intermittent, the diagnostic code may still set. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
    • The following conditions may cause an intermittent malfunction to occur:
       - Inspect for a short to battery voltage in the courtesy lamps supply voltage circuit.
       - Inspect for a short to ground in the courtesy lamps supply voltage circuit.
       - Inspect for a short to ground in the battery positive voltage circuit that feeds the courtesy lamps.
       - Inspect for an open in the battery positive voltage circuit that feeds the courtesy lamps.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Always perform the lighting diagnostic system check before attempting to diagnose the DTC.

    2.

  2. Operation of the interior lamps determines if the courtesy lamps supply voltage circuit is energized.

  3. Operation of the inadvertent power feature determines if the courtesy lamps supply voltage circuit de-energizes after the time out period.

  4. Tests for battery positive voltage at the BCM.

    5.

  5. Tests the battery positive voltage circuit of the BCM for a short to ground.

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

1

Did you perform the lighting diagnostic system check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Turn the ignition switch to RUN.
  2. Turn the Interior Lamps Override Switch ON in order to enable the interior lamps.
  3. Turn on any of the following lamps:
    4. • The LF roof rail reading lamp
    • The LR roof rail reading lamp
    • The RR roof rail reading lamp
    • The LH vanity mirror lamp
    • The RH vanity mirror lamp
    • The IP compartment lamp

Do any of the lamps light?

Go to Step 3

Go to Step 4

3

  1. Turn on both vanity mirror lamp.
  2. Turn off all other interior lamps.
  3. Turn the ignition switch to the OFF position and remove the key from the ignition.
  4. Close all the doors.
  5. Wait for the inadvertent power feature to time out and disable the vanity lamp.

Does the inadvertent power feature time out after ten minutes?

Go to Diagnostic Aids

Go to Step 9

4

Inspect the CTSY LAMP fuse for an open.

Is the CTSY LAMP fuse open?

Go to Step 6

Go to Step 5

5

  1. Disconnect the BCM connector C1.
  2. With a test lamp that is connected to ground, probe the battery positive voltage circuit of the BCM connector that is fed by the CTSY LAMP fuse.

Does the test lamp illuminate?

Go to Step 8

Go to Step 11

6

  1. Disconnect the BCM connector C1.
  2. With a test lamp that is connected to battery voltage, probe the battery positive voltage circuit of the BCM connector that is feed by the CTSY LAMP fuse.

Does the test lamp illuminate?

Go to Step 12

Go to Step 7

7
  1. Connect a 10 amp fused jumper between the courtesy lamps supply voltage circuit and battery voltage.
  2. Turn on any of the interior lamps switches.

Does the interior lamp illuminate?

Go to Step 10

Go to Step 13

8

Test for an open in the courtesy lamps supply voltage circuit of the BCM. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 10

9

Test for a short to battery voltage in the courtesy lamps supply voltage circuit of the BCM. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 10

10

Inspect for poor connections at the BCM connector. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 14

11

Repair an open in the battery positive voltage circuit of the Body Control Module (BCM). Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Is the repair complete?

Go to Step 15

--

12

Repair a short to ground in the battery positive voltage circuit of the Body Control Module (BCM). Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Is the repair complete?

Go to Step 15

--

13

Repair a short to ground in the courtesy lamps supply voltage circuit of the Body Control Module (BCM). Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Is the repair complete?

Go to Step 15

--

14

Replace the Body Control Module (BCM). Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

Go to Step 15

--

15
  1. Turn the ignition switch to the LOCK position.
  2. Connect all of the connectors.
  3. Install all of the components.
  4. Open any vehicle door for 10 seconds.
  5. Close all the vehicle doors.
  6. Remove the Body Control Module (BCM) PRGRM Fuse.
  7. Turn the ignition switch to the ACC position. The Body Control Module (BCM) sounds the chime a number of times equivalent to the BCM type installed on the vehicle.
  8. Within 1 second, turn the ignition switch from the ACC position, to the LOCK position, back to the ACC position. The BCM sounds any DTCs stored.

Are any BCM DTCs present?

Go to Diagnostic Trouble Code (DTC) List in Body Control System

System OK