OEM 2005 Chevrolet Trailblazer Body Control Module

2005 Chevrolet Trailblazer Parts Questions & Experts Answers

• Q: How to replace the Body Control Module (BCM) on 2005 Chevrolet Trailblazer?

  A: The Body Control Module needs replacement only when the Ignition Switch is switched to off. Start disconnecting by unlinking the 40-way body wiring extension and then proceed with the 32-way tan and 24-way gray electrical connectors. Begin cap connection by plugging in the gray 24-way connector then tan 32-way connector followed by the body wiring extension 40-way. With the ignition off the bcm can detect issues and protect the courtesy lamp battery from draining but it ignores short circuits that only bcm-controlled inputs and circuits detect. Test all system circuits by placing the scanner into power down now mode to find current drains. Do not handle the body wiring extension contacts directly and keep the bcm housing closed because this part is not repairable and must be replaced as a complete unit. First step is to detach the battery negative terminal. Position the left hand second chair to its cargo setting for chevrolet trailblazer or gmc envoy while maintaining the left second row seat in place for chevrolet trailblazer ext or gmc envoy xl. Flip up the rear electrical center cover and press and hold the securing tab as you slide the bcm lock towards the vehicle interior until it reaches its full extension at 40 mm (1.6 inches). Detach the bcm from the rear electrical center when you disconnect the body wiring extension at 40 ways, tan electrical connector at 32 ways, and gray electrical connector at 24 ways. Insert the bcm slots into rear electrical center positions before placing it in place with downward pressure. Secure the bcm with the 24-way gray electrical connector, the 32-way tan electrical connector, and the 40-way body wiring extension plugged in. Push the sliding latch down to lock the bcm in place at the rear electrical center. Make sure the locking tab enters its proper location fully. Put back the rear electrical cover and move the left second seat from passenger to back position on trailblazer ext or envoy xl units. After installing the bcm finish by plugging in the negative battery and activating its programming when needed.