Gauges
Boost Pressure:
The boost pressure gauge consists of a manometer that indicates the pressure in the intake manifold. At normal pressure the needle should be vertical. An overpressure or vacuum is indicated to the right and left of vertical respectively. Measurement range 0.2 - 2.0 bar (3 - 30 lbf/Sq. in). The boost pressure gauge is connected to the engine intake manifold by a hose.
Fuel Level/Gauge:
This system consists of a [1][2]fuel level sensor and fuel gauge. The fuel gauge measures the quantity of fuel corresponding 63 liters (16.6 US gal) within the range; full fuel tank (70 liters (18.5 US gal)) to remaining fuel 7 liters (1.8 US gal).
The sensor has a float. The position of the float (depending on the quantity of fuel) acts on the resistance in the circuit. When the float is in its upper position, resistance is approx. 10 Ohms. This rises successively to approx. 325 Ohms when the float is in its lower position. A yellow warning lamp lights when there are approx. 8 liters (2.1 US gal) of fuel left in the fuel tank.
When the fuel gauge is connected (the ignition is switched on) it should display the correct quantity of fuel within 3 seconds.
NOTE: When filling fuel with the ignition on or the engine running it takes a long time for the fuel gauge to reach the correct level because of the built-in delay. The fuel gauge displays the correct level when the ignition is switched off and then on again.
The low fuel level warning lamp also lights when the generator (GEN) charging signal (D+) is low.
Speedometer:
The speedometer is electronic and has a trip odometer (VDO). The speedometer receives a signal from the ABS control module which in turn receives a signal from the front ABS sensors. The number of pulses per kilometer is 25,793 (41500/mile) and corresponds to a tire circumference of 1,861 (6,102 ft) meters. The speedometer has two short-circuit proof outputs for the vehicle speed sensor (VSS) signal. One has the same frequency as the input signal (48 pulses/revolution) and one has a frequency corresponding to 1/4 of the input signal: 12 pulses/revolution. The frequency of the output vehicle speed sensor (VSS) signal is proportional to the frequency of the input signal and is used for the following systems:
Output, 12-pulse:
Ignition system
Fuel injection system
Cruise control
Audio
Output, 48-pulse:
Trip computer
ECC
Speedometer 12 Pulse Output:
It is important that accessories are connected to the output for the 12 pulse signal, see image. The incorrect connection of accessories can cause speedometer failure and diagnostic trouble codes (DTCs) in the fuel, ignition or automatic transmission control systems.
Tachometer (RPM):
The tachometer indicates the engine speed (RPM). The tachometer receives its control signal from the ignition control module (ICM). The ignition control module (ICM) receives information about engine speed (RPM) from the engine speed (RPM) sensor located at the flywheel.
Vehicle is equipped with a central engine coolant temperature (ECT) sensor signal which is used by the temperature gauge. The analogue temperature sensor voltage is converted to a frequency modulated signal by the ignition control module (ICM). CENT signal frequency decreases with increasing temperature.