The instrument cluster (2) for this model is an Electro-
Mechanical Instrument Cluster (EMIC) that is located
in the instrument panel (1) above the steering column
opening, directly in front of the driver. The remainder
of the EMIC, including the mounts and the electrical
connections, are concealed within the instrument
panel

behind

the

cluster

bezel.

Besides

analog

gauges and indicators, the EMIC module incorporates
two blue-green digital Vacuum Fluorescent Display
(VFD) units for displaying odometer/trip odometer
information, engine hours, automatic transmission
gear selector position (PRNDL), several warning or
reminder indications and certain diagnostic informa-
tion. The instrument cluster for this model also
includes the hardware and software necessary to
serve as the electronic body control module and is
sometimes referred to as the Cab Compartment Node
or CCN.

The EMIC gauges and indicators are visible through a
dedicated opening in the cluster bezel on the instru-
ment panel and are protected by a clear plastic cluster
lens that is integral to a cluster lens, hood and mask
unit (4). Just behind the cluster lens is the cluster
hood and an integral cluster mask, which are con-
structed of molded black plastic. The cluster hood
serves as a visor and shields the face of the cluster
from ambient light and reflections to reduce glare,
while the cluster mask serves to separate and define
the individual gauges and indicators of the EMIC. A
black plastic odometer/trip odometer switch button
protrudes through dedicated holes in the cluster mask
and the cluster lens, located near the lower edge of
the cluster just to the left of the tachometer. The
molded plastic EMIC lens, hood and mask unit has
four integral mounting tabs, one each on the upper
and lower outboard corners of the unit. These mounting tabs are used to secure the EMIC to the molded plastic
instrument panel cluster carrier with four screws.

The rear of the cluster housing and the EMIC electronic circuitry are protected by a molded plastic rear cover (2),
which is secured to the cluster housing with a single screw (1), while eight screws installed around the outside
perimeter of the rear cover secure it to the cluster lens, hood and mask unit. The rear cover includes clearance
holes for service access to each of the eleven incandescent bulb and bulb holder units installed on the cluster circuit
board for general illumination lighting and for the cluster connector receptacles. The connector receptacles on the
back of the cluster electronic circuit board connect the EMIC to the vehicle electrical system through three take outs
with connectors from the instrument panel wire harness. The EMIC also has an integral interface connector on the

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back of the cluster circuit board that joins it to the optional external Remote Keyless Entry (RKE) module through a
connector receptacle that is integral to that unit. The rear cover includes a molded receptacle and two latch features
to secure the RKE module on vehicles that are so equipped.

Sandwiched between the rear cover and the lens, hood and mask unit is the cluster housing (3). The molded plastic
cluster housing serves as the carrier for the cluster circuit board and circuitry, the cluster connector receptacles, the
RKE interface connector, the gauges, a Light Emitting Diode (LED) for each cluster indicator, two VFD units, an
audible tone transducer, the cluster overlay, the gauge pointers, the odometer/trip odometer switch and the switch
button.

The cluster overlay is a laminated plastic unit. The dark, visible, outer surface of the overlay is marked with all of the
gauge dial faces and graduations, but this layer is also translucent. The darkness of this outer layer prevents the
cluster from appearing cluttered or busy by concealing the cluster indicators that are not illuminated, while the trans-
lucence of this layer allows those indicators and icons that are illuminated to be readily visible. The underlying layer
of the overlay is opaque and allows light from the LED for each of the various indicators and the incandescent
illumination lamps behind it to be visible through the outer layer of the overlay only through predetermined stencil-
like cutouts. A rectangular opening in the overlay at the base of both the speedometer and the tachometer dial faces
has a smoked clear lens through which the illuminated VFD units can be viewed.

Several versions of the EMIC module are offered on this model. These versions accommodate all of the variations
of optional equipment and regulatory requirements for the various markets in which the vehicle will be offered. The
microprocessor-based EMIC utilizes integrated circuitry and information carried on the Programmable Communica-
tions Interface (PCI) data bus along with several hard wired analog and multiplexed inputs to monitor sensors and
switches throughout the vehicle. In response to those inputs, the internal circuitry and programming of the EMIC
allow it to control and integrate many electronic functions and features of the vehicle through both hard wired out-
puts and the transmission of electronic message outputs to other electronic modules in the vehicle over the PCI
data bus. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/COMMUNICATION - DESCRIPTION -
PCI BUS).

Besides typical instrument cluster gauge and indicator support, the electronic functions and features that the EMIC
supports or controls include the following:

•

Audible Warnings - The EMIC electronic circuit board is equipped with an audible tone transducer and pro-
gramming that allows it to provide various audible alerts to the vehicle operator, including chime tones and
beep tones. An electromechanical relay is also soldered onto the circuit board to produce audible clicks that
emulate the sound of a conventional turn signal or hazard warning flasher. (Refer to 8 - ELECTRICAL/CHIME/
BUZZER - DESCRIPTION).

•

Audio System Cabin Equalization - The EMIC stores the cabin equalization curves for various optional
speaker system architectures for use by the radio. The EMIC provides this information when requested by the
radio over the PCI data bus. Changing the cabin equalization settings of the EMIC requires the use of a diag-
nostic scan tool. Refer to the appropriate diagnostic information.

•

Brake Lamp Control - The EMIC provides electronic brake lamp request messages to the Front Control Mod-
ule (FCM) located on the Integrated Power Module (IPM) for brake lamp control, excluding control of the Cen-
ter High Mounted Stop Lamp (CHMSL), which remains controlled by a direct hard wired output of the brake
lamp switch.

•

Brake Transmission Shift Interlock Control - On vehicles with an optional automatic transmission the EMIC
monitors inputs from the brake lamp switch, ignition switch, and the Transmission Range Sensor (TRS), then
controls a high-side driver output to operate the Brake Transmission Shift Interlock (BTSI) solenoid that locks
and unlocks the automatic transmission gearshift selector lever on the steering column.

•

Cargo Lamp Control - The EMIC provides direct control of cargo lamp operation with a load shedding (battery
saver) feature which will automatically turn off the cargo lamp if it remains on after a timed interval.

•

Central Locking - The EMIC provides support for the central locking feature of the power lock system. This
feature will lock or unlock all doors based upon the input from the door cylinder lock switch on the driver side
front door. A door cylinder lock switch is used only on models equipped with the optional Vehicle Theft Security
System (VTSS).

•

Enhanced Accident Response - The EMIC monitors an input from the Airbag Control Module (ACM) and,
following an airbag deployment, will immediately disable the power lock output, unlock all doors by activating
the power unlock output, then enables the power lock output if the power lock switch input remains inactive for
two seconds. The EMIC also monitors an input from the Powertrain Control Module (PCM) to automatically
turn on the interior lighting after an airbag deployment event, ten seconds after the vehicle speed is zero. The
interior lighting remains illuminated until the ignition switch is turned to the Off position, at which time the inte-

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