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Fuel gauge (MIU 2)

Fuel gauge (MIU 2)

When the ignition switch is turned to the Drive position, positive voltage is supplied from fuse 17 to pin 55 of the main instrument display panel for further distribution to:


• the fuel level gauge

• the low fuel warning lamp

This tells the driver how much fuel is left in the tank.

The level sensor in the fuel tank has a variable resistor whose resistance corresponds to the level sensed by the sensor's float in the tank.

The sensor is connected to pin 11 of the main instrument display panel's control module which reads the resistance of the sensor and controls the voltage supplied to the fuel gauge so that its needle corresponds to this resistance.

When the fuel remaining in the tank is down to about 8 litres, the low fuel warning lamp is connected to ground via pin 12 of the main instrument display panel.

The information is also made available to other systems via pins 3 and 4.

On cars with OBDII, pin 32 connects the input of the respective engine control module to ground.


Fuel consumption

The main instrument display panel receives information from the engine management system on how much fuel has been consumed since the last time the ignition was switched on.

This information is then available on pins 3 and 4 for the SID unit, which uses it for the trip computer.