Vehicle speed sensor

VEHICLE SPEED SENSOR

SWF B451

BORLETTI TGK

SO.GE.MI.

The sensor is located on the differential output, near the left half-axle joint. It sends information on vehicle speed to the control unit: the signal is also used to operate the speedometer.

The sensor operates on the principle of the Hall effect (see section on "engine timing sensor") and transmits 16 pulses/revolution. Vehicle speed can therefore be calculated from pulse frequency.

Removing - refitting

Disconnect electrical connection and remove the sensor.

Tightening torque 0.8 daNm

SAFETY AND VENTILATION VALVE

This valve is located in the fuel filler cap and performs the following functions according to the pressure level in the tank:

• When the pressure inside the tank exceeds 0.13 - 0.18 bar, excess fuel vapours are vented to the outside (pressure-relief function).
• If, on the other hand, a vacuum builds up inside the tank, equivalent to 0.020 - 0.030 bar, air is taken into the tank (ventilation function).