Body Control Module

The Body Control Module (BCM) supplies vehicle occupants with visual and audible information and controls various vehicle functions. To provide and receive information, the module is interfaced to the vehicle's serial bus communications network (the Programmable Communication Interface or PCI bus). This network consists of the Powertrain Control Module (PCM), the Memory Heat Seat/mirror Module (MHSMM), sentry key immobilizer module (SKIM), the transmission control module (TCM), the electro/mechanical instrument cluster (MIC), the optional Overhead Travel Information System (OTIS), Airbag Control Module (ACM), Optional Antilock Brakes (ABS), the radio and the optional Automatic Temperature Control (ATC) display head. The (BCM) is operational when battery power is supplied to the module, ignition switch power is needed for ignition switched functions.




The body control module provides the following features:
Automatic headlamp and fog lamp
A/C switch status/evaporator temperature status BCM diagnostic support
Central lock and unlock (VTSS only)
Climate Control (Automatic and Manual) system support
Door ajar switch status
Door Lock Inhibit (key in ignition or headlamps/ park lamps ON)
Electronic Odometer Support Fog Lamp Control
Headlamp multiplexing control
Headlamp, Park & tail lamps with battery save feature
Headlamp Time Delay
Illuminated Entry with "fade to OFF"
Interior lighting with battery save feature
Mechanical Instrument Cluster (fuel level, dim
data, odometer & warning chime) support
Memory system (LHS and 300M)
Overhead travel information system
Power door lock multiplexing control
Rear Window Defogger Control
Remote Keyless Entry with Panic Mode
Remote power deck lid release
Rolling door lock control (customer programmable)
Sentry key immobilizer
Speed proportional steering
Vehicle Theft Security System
Wiper Control (speed sensitive with return to park)

The BCM receives information over the PCI Bus from the PCM in order to support certain features.

The required information is as follows:
- Engine RPM
- Engine Temperature
- Injector on Time and Distance Pulses
- Vehicle Speed
- Charging System Failure, Engine Temperature Limp-In, VTSS Arming Status
- Engine Model
- "Check Engine" lamp status

The BCM provides the PCM with information on the A/C switch status, battery temperature which is determined by the ambient temperature sensor and the "OK to Start" or VTSS status.

The LH has several customer programmable features which can be disabled or enabled by the customer.