Dodge Nitro. Manual - part 806

The front fog lamp indicator gives an indication to the vehicle operator whenever the front fog lamps are 
illuminated. 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 Totally Integrated Power Module 
(TIPM) over the Controller Area Network (CAN) data bus. 

The front fog lamp indicator Light Emitting Diode (LED) is completely controlled by the instrument cluster 
logic circuit, and that logic will allow this indicator to operate whenever the instrument cluster receives a 
battery current input on the fused B(+) circuit. Therefore, the LED can be illuminated regardless of the ignition 
switch position. The LED only illuminates when it is provided a path to ground by the instrument cluster 
transistor. The instrument cluster will turn ON the front fog lamp indicator for the following reasons: 



Front Fog Indicator Lamp-On Message - Each time the cluster receives an electronic front fog 
indicator lamp-ON message from the TIPM indicating the front fog lamps are turned ON, the front fog 
lamp indicator will be illuminated. The indicator remains illuminated until the cluster receives a lamp-
OFF message from the TIPM, or until the exterior lamp load shedding (battery saver) timed interval 
expires, whichever occurs first.  



Actuator Test - Each time the cluster is put through the actuator test, the front fog lamp 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 TIPM continually monitors electronic exterior lighting request messages from the Electro Mechanical 
Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN) to determine the appropriate 
outputs to the front fog lamps. The TIPM activates or deactivates the front fog lamps then sends the proper 
lamp-ON or lamp-OFF message back to the EMIC. 

For proper diagnosis of the front fog lamp system, the TIPM, the EMIC, the CAN data bus or the electronic 
communication related to front fog lamp indicator operation a diagnostic scan tool is required. Refer to the 
appropriate diagnostic information. 

FUEL GAUGE 

DESCRIPTION 

FUEL GAUGE 

 

2007 Dodge Nitro R/T 

2007 ACCESSORIES AND EQUIPMENT Instrument Cluster - Service Information - Nitro

  

Fig. 20: Fuel Gauge Display Symbol 
Courtesy of CHRYSLER LLC 

A fuel gauge is standard equipment on all instrument clusters. This gauge is located on the left side of the 
instrument cluster, left of the speedometer and the engine temperature gauge. 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 E (or Empty) to F (or Full). An International Control and Display 
Symbol icon for Fuel is located on the cluster overlay, adjacent to the hub of the gauge needle. An arrowhead 
pointed to the left side of the vehicle is imprinted on the cluster overlay next to the Fuel icon on the gauge to 
provide the driver with a reminder as to the location of the fuel filler access. 

The fuel gauge graphics are white, gray and black against a black field except for a single red graduation at the 
low 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 fuel gauge is serviced as a unit with the instrument cluster. 

OPERATION 

FUEL GAUGE 

The fuel gauge gives an indication to the vehicle operator of the level of fuel in the fuel tank. This gauge is 
controlled by the instrument cluster circuit board based upon cluster programming and electronic fuel level 
messages received by the cluster from the Totally Integrated Power Module (TIPM) over the Controller Area 
Network (CAN) data bus. 

The fuel 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 

 

2007 Dodge Nitro R/T 

2007 ACCESSORIES AND EQUIPMENT Instrument Cluster - Service Information - Nitro

  

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: 



Fuel Level Message - The TIPM provides a constant current source to the fuel level sending unit and 
monitors a return input on a fuel level sense circuit. The resistance through the fuel level sending unit 
increases as the fuel level rises and decreases as the fuel level falls causing changes in the fuel level sense 
input voltage. The TIPM then sends the appropriate electronic fuel level messages to the cluster. The 
cluster programming applies an algorithm to calculate the proper fuel gauge needle position based upon 
the fuel level message input, then moves the gauge needle to the proper relative position on the gauge 
scale. This algorithm is used to dampen gauge needle movement against the negative effect that fuel 
sloshing within the fuel tank can have on accurate inputs from the fuel tank sending unit to the TIPM.  



Less Than 11 Percent Tank Full Message - Each time the fuel level message to the cluster indicates the 
fuel tank is about 11 percent full or less for 10 consecutive seconds and the vehicle speed is zero, or for 
60 consecutive seconds and the vehicle speed is greater than zero, the gauge needle is moved to about the 
one-sixteenth graduation on the gauge scale, the low fuel indicator is illuminated, and a single chime tone 
is sounded. The low fuel indicator remains illuminated until the fuel level message indicates that the fuel 
tank is greater than about 14 percent full for 10 consecutive seconds and the vehicle speed is zero, or for 
60 consecutive seconds and the vehicle speed is greater than zero, 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 low fuel indicator is cycled OFF and then ON again by the appropriate messages from the 
TIPM.  



Less Than Empty Stop Message - Each time the cluster receives a fuel level message indicating the fuel 
level in the fuel tank is less than the E (or Empty) gauge needle stop position for five consecutive 
seconds, the gauge needle is moved to the low end of the gauge scale and the low fuel indicator is 
illuminated immediately. This input would indicate that the fuel level sense input to the TIPM is a short 
circuit.  



More Than Full Stop Message - Each time the cluster receives a fuel level message indicating the fuel 
level in the fuel tank is more than the F (or Full) gauge needle stop position for five consecutive seconds, 
the gauge needle is moved to the low end of the gauge scale and the low fuel indicator is illuminated 
immediately. This input would indicate that the fuel level sense input to the TIPM is an open circuit.  



Actuator Test - Each time the cluster is put through the actuator test, the fuel 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 TIPM continually monitors the fuel tank sending unit to determine the level of fuel in the fuel tank. The 
TIPM then sends the proper electronic fuel level message to the Electro Mechanical Instrument Cluster (EMIC) 
(also known as the Cab Compartment Node/CCN) and other electronic modules in the vehicle over the 
Controller Area Network (CAN) data bus. The TIPM will store a Diagnostic Trouble Code (DTC) for any fault 
detected in the fuel level sense circuit. 

For proper diagnosis of the fuel tank sending unit, the TIPM, the EMIC, the CAN data bus or the electronic 
communication related to fuel gauge operation or fuel level data processing a diagnostic scan tool is required. 
Refer to the appropriate diagnostic information. 

GAS CAP INDICATOR 

 

2007 Dodge Nitro R/T 

2007 ACCESSORIES AND EQUIPMENT Instrument Cluster - Service Information - Nitro

  

DESCRIPTION 

GAS CAP INDICATOR 

A gas cap indicator is standard equipment on all instrument clusters. However, on vehicles equipped with the 
optional diesel engine, as well as those manufactured for the Chinese market, this indicator is electronically 
disabled. The gas cap indication appears within the odometer Vacuum Fluorescent Display (VFD) unit. The gas 
cap indicator consists of a textual gas cap message which appears in place of the odometer information in the 
odometer display. 

The odometer VFD is soldered onto the cluster electronic circuit board, and is visible through a window with a 
smoked clear lens located on the lower edge of the tachometer gauge dial face of the cluster overlay. The dark 
lens over the VFD prevents it from being clearly visible when it is not illuminated. The gas cap textual message 
appears in the same blue-green color and at the same lighting level as the odometer information when it is 
illuminated by the instrument cluster electronic circuit board. 

The gas cap indicator is serviced as a unit with the VFD in the instrument cluster. 

OPERATION 

GAS CAP INDICATOR 

The gas cap indicator gives an indication to the vehicle operator when there is a gross leak detected in the on-
board fuel vapor recovery system. This indicator is controlled by the instrument cluster logic circuit based upon 
cluster programming and electronic messages received over the Controller Area Network (CAN) data bus from 
the Powertrain Control Module (PCM). 

The gas cap indicator function of the odometer Vacuum Fluorescent Display (VFD) unit 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 odometer VFD gas cap indication will always be OFF when the ignition switch is in any position 
except ON or START. The instrument cluster will turn ON the gas cap indicator for the following reasons: 



Gas Cap Indicator Lamp-On Message - Each time the cluster receives an electronic gas cap indicator 
lamp-ON message from the PCM indicating there is a gross leak in the vapor recovery system, the gas 
cap indicator will be 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.  

The PCM continually monitors the on board vapor recovery system to determine whether there are air leaks in 
the system. 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). If the EMIC turns ON the gas 
cap indicator due to a monitored gross leak in the vapor recovery system, it may indicate that the gas cap has 
been removed or is improperly installed. 

For proper diagnosis of the on board vapor recovery system, the PCM, the EMIC, the CAN data bus or the 
electronic communication related to gas cap indicator operation a diagnostic scan tool is required. Refer to the 
appropriate diagnostic information. 

 

2007 Dodge Nitro R/T 

2007 ACCESSORIES AND EQUIPMENT Instrument Cluster - Service Information - Nitro