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DESCRIPTION
A Body Control Module (BCM) is used on this model to control and integrate many of the electronic features and functions of the vehicle. The BCM is concealed below the driver side end of the instrument panel in the passenger compartment, where it is mounted to the dash panel side of the junction block with four screws. The BCM has two external connector receptacles that receive connections from the instrument panel wire harness. The BCM also has a connector concealed on the back side of the unit that joins it directly to the circuitry within the junction block.

The BCM contains a central processing unit and interfaces with other electronic modules in the vehicle on the Programmable Communications Interface (PCI) data bus network. The PCI data bus network allows the sharing of sensor information. This helps to reduce wire harness complexity, reduce internal controller hardware, and reduce component sensor current loads. At the same time, this system provides increased reliability, enhanced diagnostics, and allows the addition of many new feature capabilities.

For diagnosis of the BCM or the PCI data bus, the use of a DRB scan tool and the proper Diagnostic Procedures are recommended. The BCM can only be serviced by an authorized electronic warranty repair station. Refer to the latest version of the Chrysler Corporation Warranty Policies and Procedures for a current listing of authorized electronic repair stations.

Some of the functions and features that the BCM supports or controls, include:
- Chimes
- Automatic headlamp control
- Headlamp delay
- Headlamps on with ignition off and driver door open warning
- Key in ignition with ignition off and driver door open warning
- Automatic funeral or parade mode
- Panel lamp dimming
- Vehicle Theft Security System (VTSS)
- Illuminated entry
- Heated rear window and heated outside mirror control
- Intermittent wipe control
- Monitoring and transmitting rear door, liftgate, and liftgate flip-up glass ajar data
- Monitoring and transmitting outside ambient temperature data
- Monitoring and transmitting air conditioning select switch data
- Courtesy lamp time-out
- Door lock inhibit
- Electronic odometer and trip odometer
- Brake warning lamp
- Check gauges lamp
- High beam indicator lamp
- Seatbelt reminder lamp and chime
- Speed sensitive intermittent wipe
- Fog lamp control
- Electro-Mechanical Instrument Cluster
- BCM diagnostic support
- Electronic Vehicle Information Center (EVIC) support
- Customer programmable features, including:
- Auto door locks
- Horn chirp upon door lock with Remote Keyless Entry (RKE)
- Low fuel warning chime
- Headlights on with wipers (with auto headlamps only)
- Intermittent wipe and low speed wiper control
- Wiper system status
- Ignition ON/OFF timer
- VF displays synchronization
- Rear door and liftgate ajar status
- Acquisition & transmission of external temperature
- A/C select switch status
- Courtesy lamps (including ignition halo) with fade to OFF feature
- Reading lights/glove box lamp load shedding control
- Exterior lighting control including automatic headlamps fog lamp control and parking lamps
- Exterior lamp status
- Headlamp time delay upon ignition OFF and head-lamps switch OFF
- Instrument panel dimming
- Vehicle theft security system with panic & horn and hazard lamp activation
- Door lock inhibit (key in ignition or headlamps/park lamps ON)
- Brake fluid level switch/park brake switch interface
- Seatbelt reminder
- Speed sensitive intermittent wipe control
- Remote radio switch interface to radio
- Vehicle ignition status
- BCM self diagnostics
- Liftgate courtesy lamp disable
- Rear window defogger control
- Accessory delay control (windows and sunroof)
- Fuel economy and distance to empty (DTE) calculations
- Heated seat switch status
- Exterior lamp load shed
- Support of EVIC programmable features

The BCM provides the following new features:

Full control of all exterior and interior lamps including these features:
- A Battery Saver automatically turns OFF all exterior and interior lamps within 8 minutes after the ignition is turned OFF if they are not turned OFF by the driver. This includes the front and rear reading/courtesy lamps and the cargo area dome lamp even if they are turned ON manually.
- Theater-style interior lighting dims gradually when the doors are closed.
- Interior courtesy lamp operation may be "defeated" using the dimmer control ring on the left stalk switch.
- Instrument panel light intensity may be maximized for daytime visibility with the head lamps or parking lights by using the dimmer control ring on the left stalk switch.

A refined Accessary/Sunroof Delay allows operation of the sunroof as well as the power windows In addition the time has been extended from 30 to 45 seconds after the ignition is Switched OFF for added convenience. As in the past the delay terminates (window and/or sunroof ceases) if a door is opened which helps protect occupants from possible injury.

Beep tones for warnings and programming actions associated with the Sentry Key Immobilizer system and the EVIC.

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 and battery temperature
- Injector on time and distance pulses
- Vehicle speed
- Engine Model
- Fuel tank level
- Vehicle identification number

The BCM provides the PCM with information on the A/C switch status.

OPERATION
The functions and features provided by the BCM are possible because of its hard wired inputs and outputs, as well as the resources it shares with other electronic modules in the vehicle through its communication over the PCI data bus network. The BCM uses its internal programming and all of these inputs to decide which functions it should perform and both the standard and optional features it should provide. Refer to Body and Frame/ELECTRONIC VEHICLE INFORMATION CENTER PROGRAMMING for more information on the customer programmable feature options.

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 communication network (Programmable Communication Interface or PCI bus). This network consists of the powertrain control module (PCM) the Memory/Heated Seat Module (MHSM, MSM, or HSM), the Sentry Key Immobilizer Module (SKIM), the Transmission Control Module (TCM), the Electro/Mechanical Instrument Cluster (MIC), the Driver Door Module (DDM), the Passenger Door Module (PDM), the Airbag Control Module (ACM), the Antilock Brake Module (ABS), the optional Electronic Vehicle Information Center (EVIC), the optional PCI radio and the optional Automatic Zone Control Module (AZC). The BCM is operational when battery power is supplied to the module ignition switch power is needed for ignition switched functions.

The 1999 WJ has several programmable features which can be enabled/disabled by using the EVIC or the DRB III.