Functional Description

Functional Description

The rpm signal is supplied to the instrument cluster: from the engine injection control unit S11 which receives an "engine rpm" signal from sensor S31. The signal reaches the cluster C10 at pin 2 of connector A.

The speedometer signal is supplied by the speedometer sensor L17: this is fitted on the gearbox and detects the speed of the car at all times. This device is a pulse generator which generates and processes a signal that is proportionate with the speed

of the camshaft at the gearbox output, therefore with that of the wheels: it is a "square-wave".

The sensor L17 is supplied at pin 3 with stabilised voltage through an electronic device inside the instrument cluster (from pin 5 of connector A of C10); pin 1 is connected to earth G53b, while the tachometric signal (proportionate with the speed of the car leaves pin 2 and is sent to the instrument cluster C10 at pin 11 of connector A, and from here to the electronic device that operates the speedometer and the two mileage recorders (total and trip).