Functional Operation
Body ControllerThere are three body controllers available in 1992: the "base" controller and two "premium" body controllers. Which "premium" controller the vehicle has depends on the presence of an electronic instrument cluster.
The body controller provides power and ground for a variety of systems. It uses a voltage drop to monitor these systems.
The body controller is the only module that has the capability of providing both bias and termination on the CCD bus system.
The body controller receives information from the engine node about brake fluid level, engine coolant level, and engine oil level.
The body controller is used to store odometer information displayed in the electronic instrument cluster (see the "Electronic Instrument Cluster" description later in this section).
NOTE: When replacement of the body controller is required, contact your service center to obtain an exchange body controller.
Electronic Instrument Cluster
The electronic instrument cluster includes a digital speedometer, odometer, oil pressure gauge, coolant temperature gauge, fuel gauge, and voltage gauge. It also has a series of warning indicator lamps to provide the driver with all the necessary information to ensure that the vehicle is in perfect operating condition.
The electronic instrument cluster receives virtually all of the information for its displays from the body controller and the engine controller via the CCD bus system.
The electronic instrument cluster has two forms of diagnostic routines that are used to isolate problems within the cluster. Self-diagnostics use the "TRIP" and "TRIP RESET" buttons for access, and CCD bus diagnostic routines require the use of the DRBII diagnostic readout box.
Successful completion of the self-diagnostic test indicates that the problem is in the CCD bus, interfacing modules, connectors, wiring harnesses, or sensors outside the cluster.
The body controller (not the electronic instrument cluster) stores the odometer information that is displayed on the instrument cluster. Therefore, when replacement of the electronic cluster is required, the odometer reading will not be affected.
EVIC Head Monitor
The Electronic Vehicle Information Center (EVIC) module is located in the overhead console. It displays to the driver such information as time, outside temperature, compass direction, and fuel economy.
The EVIC head monitors information provided by the body controller, engine compartment node, and engine controller. Any failure of a monitored system results in a warning message on the EVIC head monitor.
The manual compass calibration procedure has been replaced by a continuous and automatic procedure that is performed by the engine node. Automatic calibration does not require operator interface.
Mechanical Instrument Cluster
The mechanical instrument cluster (MIC) operates independently with the exception of three functions controlled by the body controller. These functions are:
Seat Belt Warning Lamp: The body controller turns on the seat belt warning lamp for approximately six seconds when the ignition is turned on.
Low Fuel Warning Lamp: The body controller turns on the low fuel lamp when the fuel level drops to approximately 3.2 gallons including tank reserve.
Check Gauges Lamp: The body controller turns on the "CHECK GAGES" lamp when the engine controller issues a high temperature warning or a charging system failure via the CCD bus system.