The instrument cluster (3) for this model is an Electro-
Mechanical Instrument Cluster (EMIC) that is located
in the instrument panel 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 (2). Besides analog
gauges and indicators, the EMIC module incorporates
two blue-green digital Vacuum Fluorescent Display
(VFD) units. One is for displaying odometer/trip odom-
eter information, engine hours, automatic transmission
gear selector position (PRNDL), several warning or
reminder indications and certain diagnostic informa-
tion. The second is the Electronic Vehicle Information
Center (EVIC) display that will display things such as
compass/temperature, miles per gallon, average fuel
economy, distance till empty, etc. The instrument clus-
ter for this model also includes the hardware and soft-
ware necessary to serve as the electronic body control
module and is sometimes referred to as the Cab Com-
partment Node or CCN.

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INSTRUMENT CLUSTER - SERVICE INFORMATION

The EMIC gauges and indicators (5) are visible
through a dedicated opening in the cluster bezel on
the instrument panel and are protected by a clear
plastic cluster lens (3), and the integral hood. The
cluster hood serves as a visor and shields the face of
the cluster from ambient light and reflections to reduce
glare. The molded plastic EMIC lens, hood and mask
unit has two integral mounting tabs on the upper
edges 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 elec-
tronic circuitry are protected by a molded plastic rear
cover (1), which is secured to the cluster housing. The
rear cover includes clearance holes 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 houses four analog gauges and has provisions for up to twenty-five indicators. Some of the EMIC indi-
cators are automatically configured when the EMIC is connected to the vehicle electrical system for compatibility
with certain optional equipment or equipment required for regulatory purposes in certain markets. While each EMIC
may have provisions for indicators to support every available option, the configurable indicators will not be functional
in a vehicle that does not have the equipment that an indicator supports.

The EMIC includes the following analog gauges:

•

Engine Temperature Gauge (13)

•

Fuel Gauge (21)

•

Speedometer (1)

•

Tachometer (8)

The EMIC includes the following VFD units:

•

Gear Selector/Odometer/Trip A B/engine hours (20)

•

Electronic Vehicle Information Center (EVIC) Display (14) - This displays the customer programmable fea-
tures and status of them, the “Check Gauges” warning message, and the door ajar indication.

INSTRUMENT CLUSTER - SERVICE INFORMATION

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The EMIC includes provisions for the following indicators:

•

Airbag Indicator (6)

•

Antilock Brake System (ABS) Indicator (7)

•

Brake Indicator (2)

•

Charging Indicator (24)

•

Cruise Indicator (18)

•

Door Ajar Indicator (14 - within the EVIC VFD)

•

Electronic Throttle Control (ETC) Indicator (22)

•

Engine Temperature Indicator (13 - within temperature gauge)

•

Four-Wheel Drive Low Indicator (16)

•

Front Fog Lamp Indicator (23)

•

Gate Ajar Indicator (14 - within EVIC VFD)

•

High Beam Indicator (4)

•

Low Fuel Indicator (21 - within fuel gauge)

•

Low Oil Pressure Indicator (10)

•

Malfunction Indicator Lamp (MIL) (5)

•

Seat Belt Indicator (17)

•

Security Indicator (9)

•

Tow/Haul Indicator (15)

•

Traction Control Indicator (11)

•

Turn Signal (Right and Left) Indicators (3)

•

Washer Fluid Indicator (14 - within EVIC VFD)

Each indicator in the EMIC, except those located within a VFD unit, is illuminated by a dedicated LED that is sol-
dered onto the EMIC electronic circuit board. Cluster illumination is accomplished by a dimmable electro-lumines-
cent lamp, which illuminates each of the gauge dial faces for visibility when the exterior lighting is turned on. The
LED units and the electro-luminescent lamp unit are not available for service replacement and, if damaged or faulty,
the entire EMIC must be replaced.

Hard wired circuitry connects the EMIC to the electrical system of the vehicle. These hard wired circuits are integral
to several wire harnesses, which are routed throughout the vehicle and retained by many different methods. These
circuits may be connected to each other, to the vehicle electrical system and to the EMIC through the use of a
combination of soldered splices, splice block connectors, and many different types of wire harness terminal con-
nectors and insulators. Refer to the appropriate wiring information. The wiring information includes wiring diagrams,
proper wire and connector repair procedures, further details on wire harness routing and retention, as well as pin-
out and location views for the various wire harness connectors, splices and grounds.

The EMIC module for this model is serviced only as a complete unit. The EMIC module cannot be adjusted or
repaired. If a gauge, an LED indicator, a VFD unit, the electronic circuit board, the circuit board hardware, the clus-
ter overlay, or the EMIC housing are damaged or faulty, the entire EMIC module must be replaced. The cluster lens,
hood and mask unit is available for separate service replacement.

OPERATION

The ElectroMechanical Instrument Cluster (EMIC) in 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 following information deals primarily with the instrument cluster functions of this unit. Additional details of
the electronic body control functions of this unit may be found within the service information for the system or com-
ponent that the EMIC controls. For example: Additional details of the audible warning functions of the EMIC are
found within the Chime/Buzzer service information.

The EMIC is designed to allow the vehicle operator to monitor the conditions of many of the vehicle components
and operating systems. The gauges and indicators in the EMIC provide valuable information about the various stan-
dard and optional powertrains, fuel and emissions systems, cooling systems, lighting systems, safety systems and
many other convenience items. The EMIC is installed in the instrument panel so that all of these monitors can be
easily viewed by the vehicle operator when driving, while still allowing relative ease of access for service.

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INSTRUMENT CLUSTER - SERVICE INFORMATION

The microprocessor-based EMIC hardware and software uses various inputs to control the gauges and indicators
visible on the face of the cluster. Some of these inputs are hard wired, but most are in the form of electronic mes-
sages that are transmitted by other electronic modules over the Controller Area Network (CAN) data bus. (Refer to
8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/COMMUNICATION - OPERATION).

The EMIC microprocessor smooths the input data using algorithms to provide gauge readings that are accurate,
stable and responsive to operating conditions. These algorithms are designed to provide gauge readings during
normal operation that are consistent with customer expectations. However, when abnormal conditions exist such as
high coolant temperature, the algorithm can drive the gauge pointer to an extreme position and the microprocessor
can sound a chime through the on-board audible tone transducer to provide distinct visual and audible indications of
a problem to the vehicle operator. The EMIC may also produce audible warnings for other electronic modules in the
vehicle based upon electronic tone request messages received over the CAN data bus. Each audible warning is
intended to provide the vehicle operator with an audible alert to supplement a visual indication.

The EMIC circuitry operates on battery current received through a fused B(+) fuse on a non-switched fused B(+)
circuit, and on battery current received through a fused ignition switch output (run-start) fuse on a fused ignition
switch output (run-start) circuit. This arrangement allows the EMIC to provide some features regardless of the igni-
tion switch position, while other features will operate only with the ignition switch in the On or Start positions. The
EMIC circuitry is grounded through a ground circuit and take out of the instrument panel wire harness with an eyelet
terminal connector that is secured by a ground screw to a ground location near the center of the instrument panel
structural support.

GAUGES

All gauges receive battery current through the EMIC circuitry only when the ignition switch is in the On or Start
positions. With the ignition switch in the Off position battery current is not supplied to any gauges, and the EMIC
circuitry is programmed to move all of the gauge needles back to the low end of their respective scales. Therefore,
the gauges do not accurately indicate any vehicle condition unless the ignition switch is in the On or Start positions.

All of the EMIC gauges are air core magnetic units. Two fixed electromagnetic coils are located within each gauge.
These coils are wrapped at right angles to each other around a movable permanent magnet. The movable magnet
is suspended within the coils on one end of a pivot shaft, while the gauge needle is attached to the other end of the
shaft. One of the coils has a fixed current flowing through it to maintain a constant magnetic field strength. Current
flow through the second coil changes, which causes changes in its magnetic field strength. The current flowing
through the second coil is changed by the EMIC circuitry in response to messages received over the CAN data bus.
The gauge needle moves as the movable permanent magnet aligns itself to the changing magnetic fields created
around it by the electromagnets.

Proper testing of the CAN data bus and the electronic data bus message inputs to the EMIC that control each
gauge require the use of a diagnostic scan tool. Refer to the appropriate diagnostic information. Specific operation
details for each gauge may be found elsewhere in this service information.

VACUUM-FLUORESCENT DISPLAYS

The Vacuum-Fluorescent Display (VFD) units are soldered to the EMIC electronic circuit board. With the ignition
switch in the Off or Accessory positions, the odometer and EVIC VFD’s are activated when the driver door is
opened (Rental Car mode) and is deactivated when the driver door is closed. Otherwise, the display units are active
when the ignition switch is in the On or Start positions, and inactive when the ignition switch is in the Off or Acces-
sory positions.

The illumination intensity of the VFD units are controlled by the EMIC circuitry based upon an input from the head-
lamp switch and a dimming level input received from the panel dimmer switch. The EMIC synchronizes the illumi-
nation intensity of other VFD units with that of the units in the EMIC by sending electronic dimming level messages
to other electronic modules in the vehicle over the CAN data bus.

Proper testing of the CAN data bus and the electronic data bus message inputs to the EMIC that control some of
the VFD functions requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information. Spe-
cific operation details for the odometer, the trip odometer, the gear selector indicator and the various warning and
reminder indicator functions of the VFD unit may be found elsewhere in this service information. The scan tool will
cycle through all the VFD segments during the “CCN Actuator Test.”

INSTRUMENT CLUSTER - SERVICE INFORMATION

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