Rpm Sensor - Fiat 1998 Marea Service Manual

Marea-Marea
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RPM SENSOR

The rpm sensor is fitted on the cylinder
block/crankcase and is facing the flywheel on
the crankshaft.
The sensor is the inductive type, i.e. it operates
through the variation in the magnetic field
produced by the passing of the flywheel teeth
(60-2 teeth) in front of the sensor element.
The injection control unit uses the rpm sensor
signal to determine the angular position of the
crankshaft and the speed.
Operation
The passage from full to empty, due to
whether or not there is a tooth, determines a
variation in the magnetic flow sufficient to
produce an alternating voltage from
counting of the teeth on the flywheel.
The peak output voltage value from the rpm
sensor depends, all things being equal, on the
distance between the sensor and the flywheel
teeth.
1. Metal bushing
2. Permanent magnet
3. Sensor casing
4. Winding
5. Core
6. Flywheel
7. Electrical connection
To obtain correct signals, the distance between
the flywheel and the sensor (gap) should be
between 0.8 and 1.5 mm.
This distance cannot be adjusted therefore if
the gap measured is outside of the tolerance,
check the condition of the sensor and the fly-
wheel.
Winding resistance: 860 Ohm ±110% at 20
1. Maximum magnetic flow
2. Minimum mangetic flow
3. Alternating voltage
Engine
Fuel system
10.
the
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