Dodge Nitro. Manual — part 804



Cruise Indicator Lamp-On Message - Each time the cluster receives an electronic cruise indicator
lamp-ON message from the PCM indicating the speed control system is ON, the cruise indicator is
illuminated. The indicator remains illuminated until the cluster receives a lamp-OFF message from the
PCM, or until the ignition switch is turned to the OFF position, whichever occurs first.



Actuator Test - Each time the cluster is put through the actuator test, the cruise indicator will be turned
ON, then OFF again during the Vacuum Fluorescent Display (VFD) portion of the test in order to confirm
the functionality of the VFD and the cluster control circuitry.

The PCM continually monitors the speed control switches to determine the appropriate outputs to the speed
control servo. The PCM then sends the proper lamp-ON or lamp-OFF message to the Electro Mechanical
Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN).

For proper diagnosis of the speed control system, the PCM, the EMIC, the CAN data bus or the electronic
communication related to cruise indicator operation a diagnostic scan tool is required. Refer to the appropriate
diagnostic information.

ENGINE TEMPERATURE GAUGE

DESCRIPTION

ENGINE TEMPERATURE GAUGE

Fig. 15: Engine Temperature Gauge Icon
Courtesy of CHRYSLER LLC

An engine coolant temperature gauge is standard equipment on all instrument clusters. This gauge is located on
the left side of the instrument cluster, between the fuel gauge and the speedometer. The gauge consists of a
movable gauge needle or pointer controlled by the instrument cluster circuitry and a fixed 90 degree gauge scale
on the cluster overlay that reads bottom-to-top from C (or Cold) to H (or Hot). An International Control and
Display Symbol icon for Engine Coolant Temperature is located on the cluster overlay, adjacent to the hub of
the gauge needle.

2007 Dodge Nitro R/T

2007 ACCESSORIES AND EQUIPMENT Instrument Cluster - Service Information - Nitro

The engine coolant temperature gauge graphics are white, gray and black against a black field except for a
single red graduation at the high end of the gauge scale, making them clearly visible within the instrument
cluster in daylight. When illuminated from behind by the panel lamps dimmer controlled cluster illumination
lighting with the exterior lamps turned ON, the graphics all retain their unilluminated colors and appearance.
The orange gauge needle has internal optical illumination. Gauge illumination is provided by Light Emitting
Diode (LED) units soldered onto the instrument cluster electronic circuit board.

The engine coolant temperature gauge is serviced as a unit with the instrument cluster.

OPERATION

ENGINE TEMPERATURE GAUGE

The engine coolant temperature gauge gives an indication to the vehicle operator of the engine coolant
temperature. This gauge is controlled by the instrument cluster circuit board based upon cluster programming
and electronic messages received by the cluster from the Powertrain Control Module (PCM) over the Controller
Area Network (CAN) data bus.

The engine coolant temperature gauge is driven by an electronic stepper motor unit that receives battery current
on the instrument cluster electronic circuit board through the fused ignition switch output (run-start) circuit
whenever the ignition switch is in the ON or START positions. The cluster is programmed to move the gauge
needle back to the low end of the scale after the ignition switch is turned to the OFF position. The instrument
cluster circuitry controls the gauge needle position and provides the following features:



Engine Temperature Message - Each time the cluster receives an electronic engine temperature
message from the PCM indicating the temperature is between the low end of normal [about 41°C (105°F)
for gasoline engines, or about 28°C (82°F) for diesel engines] and the high end of normal [about 124°C
(255°F) for gasoline engines, or about 124°C (256°F) for diesel engines], the gauge needle is moved to
the actual relative temperature position on the gauge scale.



Engine Temperature Low Message - Each time the cluster receives an electronic engine temperature
message from the PCM indicating the temperature is low [at or below about 40°C (104°F) for gasoline
engines, or about 27°C (81°F) for diesel engines], the gauge needle is held below the graduation on the
far left end of the gauge scale. The gauge needle remains below the low end of the gauge scale until the
cluster receives a message from the PCM indicating that the temperature is above the low end of normal,
or until the ignition switch is turned to the OFF position, whichever occurs first.



Engine Temperature High or Critical Message - Each time the cluster receives an electronic engine
temperature message from the PCM indicating the temperature is high [at or above about 127°C (261°F)
for gasoline engines, or about 125°C (257°F) for diesel engines], the gauge needle is moved to the red
graduation at the high end of the gauge scale, the engine temperature indicator is illuminated and a single
chime tone is sounded. The gauge needle remains at the red graduation and the engine temperature
indicator remains illuminated until the cluster receives a message from the PCM indicating that the
temperature is below about 124°C (255°F), or until the ignition switch is turned to the OFF position,
whichever occurs first. The chime tone feature will only repeat during the same ignition cycle if the
engine temperature indicator is cycled OFF and then ON again by the appropriate messages from the
PCM.



Communication Error - If the cluster fails to receive an engine temperature message, it will hold the
gauge needle at the last indication for about five seconds or until the ignition switch is turned to the OFF

2007 Dodge Nitro R/T

2007 ACCESSORIES AND EQUIPMENT Instrument Cluster - Service Information - Nitro

position, whichever occurs first. After five seconds, the cluster will move the gauge needle to the low end
of the gauge scale.



Actuator Test - Each time the cluster is put through the actuator test, the engine coolant temperature
gauge needle will be swept to several calibration points on the gauge scale in a prescribed sequence in
order to confirm the functionality of the gauge and the cluster control circuitry.

The PCM continually monitors the engine coolant temperature sensor to determine the engine operating
temperature. The PCM then sends the proper messages to the Electro Mechanical Instrument Cluster (EMIC). If
the instrument cluster turns ON the engine temperature indicator due to a high or critical engine coolant
temperature gauge reading, it may indicate that the engine or the engine cooling system requires service.

For proper diagnosis of the engine coolant temperature sensor, the PCM, the EMIC, the CAN data bus or the
electronic communication related to engine coolant temperature gauge operation a diagnostic scan tool is
required. Refer to the appropriate diagnostic information.

ENGINE TEMPERATURE INDICATOR

DESCRIPTION

ENGINE TEMPERATURE INDICATOR

Fig. 16: Identifying Engine Temperature Indicator
Courtesy of CHRYSLER LLC

An engine temperature indicator is standard equipment on all instrument clusters. The engine temperature
indicator is located above the engine coolant temperature gauge needle hub on the cluster overlay, to the left of
the speedometer.

The engine temperature indicator consists of a stencil-like cutout of the International Control and Display
Symbol icon for Engine Coolant Temperature in the opaque layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents the indicator from being clearly visible when it is not illuminated. A red
Light Emitting Diode (LED) behind the cutout in the opaque layer of the overlay causes the indicator to appear
in red through the translucent outer layer of the overlay when it is illuminated from behind by the LED, which
is soldered onto the instrument cluster electronic circuit board.

2007 Dodge Nitro R/T

2007 ACCESSORIES AND EQUIPMENT Instrument Cluster - Service Information - Nitro

The engine temperature indicator is serviced as a unit with the instrument cluster.

OPERATION

ENGINE TEMPERATURE INDICATOR

The engine temperature indicator gives an indication to the vehicle operator when the engine temperature gauge
reading reflects a condition requiring immediate attention. This indicator is controlled by a transistor on the
instrument cluster circuit board based upon cluster programming and electronic messages received by the
cluster from the Powertrain Control Module (PCM) over the Controller Area Network (CAN) data bus.

The engine temperature indicator Light Emitting Diode (LED) is completely controlled by the instrument
cluster logic circuit, and that logic will only allow this indicator to operate when the instrument cluster receives
a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the LED will always be
OFF when the ignition switch is in any position except ON or START. The LED only illuminates when it is
provided a path to ground by the instrument cluster transistor. The instrument cluster will turn ON the engine
temperature indicator for the following reasons:



Bulb Test - Each time the ignition switch is turned to the ON position the engine temperature indicator is
illuminated for about two seconds as a bulb test. The entire bulb test is a function of the PCM.



Engine Temperature High or Critical Message - Each time the cluster receives an electronic engine
temperature message from the PCM indicating the temperature is high [at or above about 127°C (261°F)
for gasoline engines, or about 128°C (262°F) for diesel engines], the engine temperature indicator will be
illuminated and a single chime tone is sounded. The indicator remains illuminated until the cluster
receives a message from the PCM indicating that the temperature is below about 124°C (255°F), or until
the ignition switch is turned to the OFF position, whichever occurs first. The chime tone feature will only
repeat during the same ignition cycle if the engine temperature indicator is cycled OFF, then ON again by
the appropriate messages from the PCM.



Actuator Test - Each time the cluster is put through the actuator test, the engine temperature indicator
will be turned ON, then OFF again during the bulb check portion of the test to confirm the functionality
of the LED and the cluster control circuitry.

The PCM continually monitors the engine coolant temperature sensor to determine the engine operating
temperature. The PCM then sends the proper messages to the Electro Mechanical Instrument Cluster (EMIC)
(also known as the Cab Compartment Node/CCN). For further diagnosis of the engine temperature indicator or
the instrument cluster circuitry that controls the LED, see DIAGNOSIS AND TESTING. If the instrument
cluster turns ON the engine temperature indicator due to a high engine temperature gauge reading, it may
indicate that the engine or the engine cooling system requires service.

For proper diagnosis of the engine coolant temperature sensor, the PCM, the EMIC, the CAN data bus or the
electronic communication related to engine temperature indicator operation a diagnostic scan tool is required.
Refer to the appropriate diagnostic information.

ELECTRONIC STABILITY PROGRAM/BRAKE ASSIST SYSTEM INDICATOR

DESCRIPTION

2007 Dodge Nitro R/T

2007 ACCESSORIES AND EQUIPMENT Instrument Cluster - Service Information - Nitro