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Dodge Dakota (ND). Manual - part 275

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.

The EMIC also has a self-diagnostic actuator test capability, which will test each of the CAN bus message-controlled
functions of the cluster by lighting the appropriate indicators, positioning the gauge needles at several predeter-
mined calibration points across the gauge faces, and illuminating all segments of the gear selector/odometer/trip
odometer Vacuum-Fluorescent Display (VFD) unit. (Refer to 8 - ELECTRICAL/INSTRUMENT CLUSTER - DIAGNO-
SIS AND TESTING).

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.

The gauges are diagnosed using the EMIC self-diagnostic actuator test. (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). 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 diag-
nostic information. Specific operation details for each gauge may be found elsewhere in this service information.

VACUUM-FLUORESCENT DISPLAY

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

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

The EMIC VFD unit has several display capabilities including odometer, trip odometer, engine hours, gear selector
indication (PRNDL), several warning or reminder indications, and various diagnostic information when certain fault
conditions exist. An odometer/trip odometer switch on the EMIC circuit board is used to control some of the display
modes. This switch is actuated manually by depressing the odometer/trip odometer switch button that extends
through the lower edge of the cluster lens, just left of the minor gauge set. Actuating this switch momentarily with
the ignition switch in the On position will toggle the VFD between the odometer and trip odometer modes. Depress-
ing the switch button for about two seconds while the VFD is in the trip odometer mode will reset the trip odometer
value to zero.

While in the odometer mode with the ignition switch in the On position and the engine not running, depressing the
odometer/trip odometer switch for about six seconds will display the engine hours information. Holding this switch

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depressed while turning the ignition switch from the Off position to the On position will initiate the EMIC self-diag-
nostic actuator test. Refer to the instrument cluster diagnosis and testing service information for additional details on
this cluster function. The EMIC microprocessor remembers which display mode is active when the ignition switch is
turned to the Off position, and returns the VFD display to that mode when the ignition switch is turned On again.

The VFD unit is diagnosed using the EMIC self-diagnostic actuator test. (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). 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. Specific 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.

INDICATORS

Indicators are located in various positions within the EMIC and are all connected to the EMIC electronic circuit
board. The door ajar indicator, cargo lamp indicator, high beam indicator, and turn signal indicators operate based
upon hard wired inputs to the EMIC. The brake indicator is controlled by CAN data bus messages from the Con-
troller Antilock Brake (CAB) as well as by hard wired park brake switch inputs to the EMIC. The seatbelt indicator
is controlled by the EMIC programming, CAN data bus messages from the Occupant Restraint Controller (ORC),
and a hard wired seat belt switch input to the EMIC. The Malfunction Indicator Lamp (MIL) is normally controlled by
CAN data bus messages from the Powertrain Control Module (PCM); however, if the EMIC loses CAN data bus
communication, the EMIC circuitry will automatically turn the MIL on until CAN data bus communication is restored.
The EMIC uses CAN data bus messages from the Front Control Module (FCM), the PCM, the ORC, the CAB, and
the Sentry Key REmote Entry Module (SKREEM) to control all of the remaining indicators.

The various EMIC indicators are controlled by different strategies; some receive fused ignition switch output from
the EMIC circuitry and have a switched ground, while others are grounded through the EMIC circuitry and have a
switched battery feed. However, all indicators are completely controlled by the EMIC microprocessor based upon
various hard wired and electronic message inputs. The cruise, four low, four lock and tow/haul indicators and those
located within the VFD unit are dimmable. All other indicators are illuminated at a fixed intensity, which is not
affected by the selected illumination intensity of the electro-luminescent EMIC general illumination lamp. The illumi-
nation intensity of the dimmable indicators is synchronized with that of the EMIC general illumination lamp.

In addition, certain indicators in this instrument cluster are automatically configured or self-configured. This feature
allows the configurable indicators to be enabled by the EMIC circuitry for compatibility with certain optional equip-
ment. The EMIC defaults for the ABS indicator and airbag indicator are enabled, and these configuration settings
must be programmatically disabled in the EMIC using a diagnostic scan tool for vehicles that do not have this equip-
ment. The automatically configured or self-configured indicators remain latent in each EMIC at all times and will be
active only when the EMIC receives the appropriate CAN message inputs for that optional system or equipment.

The hard wired indicator inputs may be diagnosed using conventional diagnostic methods. However, the EMIC cir-
cuitry and CAN bus message controlled indicators are diagnosed using the EMIC self-diagnostic actuator test.
(Refer to 8 - ELECTRICAL/INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING). Proper testing of the CAN data
bus and the electronic message inputs to the EMIC that control an indicator requires the use of a diagnostic scan
tool. Refer to the appropriate diagnostic information. Specific details of the operation for each indicator may be
found elsewhere in this service information.

CLUSTER ILLUMINATION

The EMIC has a single electro-luminescent lamp that provides cluster back lighting whenever the exterior lighting is
turned On. The illumination intensity of this lamp is adjusted when the interior lighting thumbwheel on the headlamp
switch is rotated (down to dim, up to brighten) to one of six available minor detent positions. The EMIC monitors a
resistor multiplexed input from the headlamp switch on a dimmer input circuit. In response to that input, the EMIC
electronic circuitry converts a fused 12-volt input it receives on a hard wired panel lamps dimmer switch signal cir-
cuit into a 12-volt Pulse Width Modulated (PWM) output.

The EMIC uses this PWM output to control the illumination intensity of the electro-luminescent cluster illumination
lamp and the VFD unit on the EMIC circuit board, then provides a synchronized PWM output on various hard wired
fused panel lamps dimmer switch signal circuits to control and synchronize the illumination intensity of other incan-
descent illumination lamps in the vehicle. The EMIC also transmits electronic dimming level messages over the CAN
data bus to other electronic modules in the vehicle to control and synchronize the illumination intensity of their VFD
units to that of the EMIC VFD unit.

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In addition, the thumbwheel on the headlamp switch has a Parade Mode position to provide a parade or funeral
mode. The EMIC monitors the request for this mode from the headlamp switch, then transmits an electronic dim-
ming level message to illuminate all VFD units in the vehicle at full (daytime) intensity for easier visibility when
driving in daylight with the exterior lighting turned On.

The electro-luminescent lamp unit consists of layers of phosphor, carbon, idium tin oxide, and dielectric applied by
a silk-screen process between two polyester membranes and includes a short pigtail wire and connector. The lamp
pigtail wire is connected to a connector receptacle on the EMIC circuit board. The EMIC powers this lamp with an
Alternating Current (AC) rated at 80 volts rms (root mean squared) and 415 Hertz produced by a transformer on the
circuit board, which excites the phosphor particles causing them to luminesce.

The hard wired headlamp switch and panel lamps dimmer inputs to and outputs from the EMIC may be diagnosed
using conventional diagnostic methods. However, proper testing of the PWM processing of the EMIC and the elec-
tronic dimming level messages sent by the EMIC over the CAN data bus requires the use of a diagnostic scan tool.
Refer to the appropriate diagnostic information.

DIAGNOSIS AND TESTING

INSTRUMENT CLUSTER

WARNING: To avoid personal injury or death, on vehicles equipped with airbags, disable the supplemental
restraint system before attempting any steering wheel, steering column, airbag, occupant classification sys-
tem, seat belt tensioner, impact sensor, or instrument panel component diagnosis or service. Disconnect
and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge
before performing further diagnosis or service. This is the only sure way to disable the supplemental
restraint system. Failure to take the proper precautions could result in accidental airbag deployment.

If all of the instrument cluster gauges and indicators are inoperative, be certain to check the instrument cluster fused
B(+) fuse and the instrument cluster fused B(+) and ground circuits for shorts or opens. Refer to the appropriate
wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures,
details of wire harness routing and retention, connector pin-out information and location views for the various wire
harness connectors, splices and grounds.

If an individual hard wired gauge or indicator is inoperative, refer to the diagnosis and testing service information for
that specific gauge or indicator. If an individual Controller Area Network (CAN) data bus message-controlled gauge
or indicator is inoperative, perform the Actuator Test as follows:

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 clus-
ter is programmed to do this by embedding the Vehicle Identification Number (VIN) and other information
critical to proper cluster operation into electronic memory. This embedded information is learned through
electronic messages received from other electronic modules in the vehicle over the Controller Area Network
(CAN) 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 irre-
versible 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 instru-
ment cluster damage, which is not reimbursable under the terms of the product warranty. Service replace-
ment instrument clusters are provided with the correct VIN, and the certified odometer and engine hours
values embedded into 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.

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NOTE: Certain indicators in this instrument cluster are automatically configured. This feature allows those
indicators to be activated or deactivated for compatibility with certain optional equipment. If the problem
being diagnosed involves improper illumination of the cruise indicator, the electronic throttle control indi-
cator, the tow/haul indicator, the service four-wheel drive indicator, the four-wheel drive low indicator, the
four-wheel drive lock indicator, the transmission overtemp indicator, the security indicator or the gear selec-
tor indicator, disconnect and isolate the battery negative cable. After about five minutes, reconnect the bat-
tery negative cable and turn the ignition switch to the On position. The instrument cluster should
automatically relearn the equipment in the vehicle and properly configure the configurable indicators
accordingly.

ACTUATOR TEST

The instrument cluster actuator test will put the instrument cluster into its self-diagnostic mode. In this mode the
instrument cluster can perform a self-diagnostic test that will confirm that the instrument cluster circuitry, the gauges,
and the indicators are capable of operating as designed. During the actuator test the instrument cluster circuitry will
position each of the gauge needles at various calibration points and illuminate all of the segments in the Vacuum
Fluorescent Display (VFD) unit.

Successful completion of the actuator test will confirm that the instrument cluster is operational. However, there may
still be a problem with the CAN data bus, the Powertrain Control Module (PCM), the Front Control Module (FCM),
the Transmission Control Module (TCM), the Occupant Restraint Controller (ORC), the Controller Anti-lock Brake
(CAB), or the hard wired inputs to one of these electronic control modules. Use a diagnostic scan tool to diagnose
these components. Refer to the appropriate diagnostic information.

1. Begin the test with the ignition switch in the Off position.

2. Depress the odometer/trip odometer switch button.

3. While still holding the odometer/trip odometer switch button depressed, turn the ignition switch to the On position,

but do not start the engine.

4. Release the odometer/trip odometer switch button.

5. The instrument cluster will simultaneously begin to illuminate all of the operational segments in the VFD unit, and

perform a bulb check of each operational LED indicator. The VFD segments and LED indicators remain illumi-
nated as each gauge needle is swept to several calibration points and back. If a VFD segment or an LED indi-
cator fails to illuminate, or if a gauge needle fails to sweep through the calibration points and back during this
test, the instrument cluster must be replaced.

6. The actuator test is now completed. The instrument cluster will automatically exit the self-diagnostic mode and

return to normal operation at the completion of the test. The actuator test will be aborted if the ignition switch is
turned to the Off position, or if a vehicle speed message indicating that the vehicle is moving is received from the
PCM over the CAN data bus during the test.

7. Go back to Step 1 to repeat the test, if necessary.

REMOVAL

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