LR3/Disco 3
The tachometer is driven by an engine speed signal transmitted on the high speed CAN from the ECM. The signal is
derived from the Crankshaft Position (CKP) sensor. The signal is received by the instrument cluster microprocessor and
the output from the microprocessor drives the tachometer.
Two versions of the tachometer are used for petrol and diesel engine variants. The petrol engine variants use a display
which has a maximum engine speed reading of 8000 rev/min. The diesel engine variants use a display which has a
maximum engine speed reading of 6000 rev/min.
Fuel Level Gage
The fuel level gage displays the fuel tank contents. When the ignition is off, the pointer returns to the empty position.
The instrument pack is connected to two tank level sensors. One sensor is located at the front of the fuel tank and the
other is located at the rear. Each sensor uses a float operated MAgnetic Passive Position Sensor (MAPPS) for measuring
the fuel tank contents. For additional information, refer to
Fuel Tank and Lines
(310-01A Fuel Tank and Lines - 4.0L)
For additional information, refer to
Fuel Tank and Lines
(310-01B Fuel Tank and Lines - 4.4L)
For additional information, refer to
Fuel Tank and Lines
(310-01C Fuel Tank and Lines - 2.7L Diesel)
Each sensor is supplied with a reference current from the instrument cluster. The instrument cluster measures the
returned output from each sensor which is proportional to the amount of fuel in the tank and the position of the float arm.
The inclination of the vehicle, derived from a CAN message from the Electronic Park Brake (EPB) module, is also used to
calculate the fuel tank contents. The instrument cluster uses the fuel level sensor signals and the EPB module inclination
signals to accurately calculate the volume of fuel in the tank and display this on the fuel level gage. The instrument cluster
monitors the signals and updates the fuel level gage pointer position at approximately 20 second intervals. This prevents
the pointer moving continually due to fuel movement in the tank due to cornering or braking. When the ignition is off, the
pointer needle returns to the empty position.
A warning lamp is incorporated into the fuel level gage and illuminates when the fuel tank volume is at or below 10 liters
(2.19 Gallons) on petrol models and 18 liters (3.96 Gallons) on diesel models. This is accompanied by a chime from the
instrument cluster to alert the driver to the low fuel condition. On vehicles with a high line instrument cluster the low fuel
level is also displayed in the message center.
The fuel tank contents is converted into a CAN signal by the instrument cluster and transmitted on the CAN. This is used
by the fuel fired booster heater to suspend operation on diesel variants.
The following table shows the fuel tank fuel quantity and the respective pointer positions.
Engine Coolant Temperature Gage
The engine coolant temperature gage displays the engine coolant temperature to the driver. When the ignition is off the
pointer needle returns to the cold position.
The engine coolant temperature sensor is connected to the ECM which monitors the sensor signals and converts the
signals into a value for the engine coolant temperature. This information is transmitted on the high speed CAN for use by
the instrument cluster and other systems. For additional information, refer to
Electronic Engine Controls
(303-14A
Electronic Engine Controls - 4.0L)
For additional information, refer to
Electronic Engine Controls
(303-14B Electronic Engine Controls - 4.4L)
For additional information, refer to
Electronic Engine Controls
(303-14C Electronic Engine Controls - 2.7L Diesel)
The engine coolant temperature gage is the same on all pack variants. The gage has a blue segment for low
Fuel Tank Quantity (Liters)
Needle Pointer Position
4.82
EMPTY
12.5
LOW FUEL (Low fuel indicator illuminated) 4.0L V6 and 4.4L V8 only
14
LOW FUEL (Low fuel indicator illuminated) TdV6 only
25.5
ONE QUARTER FULL
45.4
HALF FULL
66.1
THREE QUARTERS FULL
79.89
FULL
