Instrument Panel, Gauges and Warning Indicators: Description and Operation
ALLDATA EDITORS NOTE
The Instrument Panel Gauges and Warning Indicators are not controlled by individual circuits. The ElectroMechanical Instrument Cluster (EMIC) assembly is driven by the BCM via the Programmable Communications Interface (PCI) data bus.
For diagnosis of the EMIC/MIC, Testing and Inspection
INSTRUMENT CLUSTER
The DR Instrument Cluster is a new type of control module that includes the hardware and software necessary to function as the cluster and the body control module. The Instrument Cluster Instrument Cluster / Carrier houses the Speedometer, Tachometer, Fuel gauge, Coolant Temperature gauge, Oil Pressure gauge, and the Voltage gauge. The cluster positions all of the gauges using PCI bus messages received from the PCM. The cluster contains certain warning indicators, depending on engine type and options Driver/Vehicle Information Display. Some of the indicators are hardwire inputs and some indicators are controlled via PCI bus messages. The warning chime tone generator is contained within the cluster. The cluster includes a Vacuum Fluorescent (VF) display for the PRNDL, Total and Trip Odometers. The VF will also display warning messages such as door ajar, low washer fluid level, engine hours, and no bus communications. The cluster has the ability to set and store DTC's, communicate on the PCI bus, display engine information, and display certain inputs using the DRB III.
Body Control Module
Information Bus
The following systems are controlled either completely by the Instrument Cluster or in conjunction with other inputs received by hardwire or via the PCI bus:
* Audible Warnings
* Brake Lamp Control
* Brake Transmission Shift Interlock (BTSI)
* Cargo Lamp Control
* Central Locking
* Door Lock Inhibit
* Enhanced Accident Response
* Exterior Lighting Control
* Exterior Lighting Fail-Safe
* Heated Seat Control
* Interior Lamp Control
* Interior Lamps - Enhanced Accident Response
* Interior Lamps Load Shedding
* Lamp Out Indicator Control
* Panel Lamps Dimming Control
* Parade Mode
* Power Locks
* Remote Keyless Entry (RKE)
* Remote Radio Switch Interface
* Rolling Door Locks
* Turn Signal and Hazard Warning Lamp Control
* Vacuum Fluorescent Display Synchronization
* Vehicle Theft Security System (VTSS)
CAUTION: Instrument clusters used in this model automatically configure themselves for compatibility with the features and optional equipment in the vehicle in which they are initially installed.
The instrument cluster is programmed to do this by embedding the Vehicle Identification Number (VIN) and other information critical to proper cluster operation in electronic memory.
This embedded information is learned through electronic messages received from other electronic modules in the vehicle over the Programmable Communications Interface (PCI) data bus, and through certain hard wired inputs received when the cluster is connected to the vehicle electrically.
Once configured, the instrument cluster memory may be irreparably damaged and certain irreversible configuration errors may occur if the cluster is connected electrically to another vehicle; or, if an electronic module from another vehicle is connected that provides data to the instrument cluster (including odometer values) that conflicts with that which was previously learned and stored.
Therefore, the practice of exchanging (swapping) instrument clusters and other electronic modules in this vehicle with those removed from another vehicle must always be avoided. Failure to observe this caution may result in instrument cluster damage, which is not reimbursable under the terms of' the product warranty. Service replacement instrument clusters are provided with the correct VIN, and the certified odometer and engine hours values embedded in cluster memory, but will otherwise be automatically configured for compatibility with the features and optional equipment in the vehicle in which they are initially installed.
Diagnostic Self Test
The Instrument Cluster is capable of performing a Diagnostic Self Test. This self test can be initiated manually by depressing and holding the trip reset button while cycling the ignition from the Off to the On position. The self test can also be activated using the DRB III. During the self test, all of the PCI bus indicators will be illuminated. The speedometer, tachometer, fuel gauge, oil pressure gauge, coolant temperature gauge, and voltage gauge will position at their calibration points. The VF display will illuminate all segments and also display the software version. The chime will sound. When the self test is complete, the cluster will return to normal operation. Turning the ignition to the Off position or the cluster detecting engine RPM greater than 0 (zero) will stop the self test.