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HOMESERVICE MANUALSCHEVROLET2003TRAILBLAZER 4.2 S, 4WDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 1648 (LIGHTING SYSTEMS)DIAGNOSTIC INFORMATION AND PROCEDURESDTC 002CIRCUIT DESCRIPTION
2003 Chevrolet TrailBlazer 4.2 S, 4WD

Circuit Description

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Circuit Description
WARNING: This page is about a different car, the 2002 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.

The body control module (BCM) controls the inadvertent load (battery rundown) protection feature. The BCM de-energizes the courtesy lights 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 lights 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 instrument panel dimmer switch is turned to the DOME position.
  • Any interior courtesy light connected to the courtesy lights supply voltage circuit 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. Vehicle with less than 15 total driven miles (24 kilometers) have a time-out of 162-198 seconds instead of 10 minutes.

RENDER: 1.0x

NO RELATED

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