Fiat 1995 Brava, Service Manual

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Bravo-Brava ifih
16v
Engine
Fuel system
10.
SYSTEM MANAGEMENT STRATEGIES
SIGNAL MANAGEMENT
During starting, the control unit recognizes the injection and ignition timing which are fundamental for
the subsequent operation of all strategies.
This recognition is implemented on the basis of the interpretation of the succession of signals coming
from the flywheel sensor on the crankshaft and from the engine timing sensor on the camshaft.
NOTE The end of the signals refers to the collection of signans coming from the sensor on the
crankshaft and the one on the camshaft which, featuring a precise reciprocal position, supply
the control unit with a synchronized sequence of signals which the control unit is capable of
recognizing.
In particular, the signals are made up as follows:
- flywheel on the crankshaft: equipped with two symmetrical sets of teeth, located at 10°, 65° and 97°,
respectively in advance of each T D C ;
- flywheel on the camshaft: equipped with two long windows and a short one, wide enough and posi-
tioned in such a way as to supply the signal as shown in the diagram.
130°
_ r
97°65° 10'
_rui_n
180°
97°65° 10
e
J U L J l
120°
I T
140'
97° 65° 10'
J U L J l
130°
3 6 0 ° 540°
97° 65° 10°
J U L - J L -
120°
J ~ L
140*
1. cylinder T D C
2. Crankshaft angles
3. Crankshaft flywheel signal (engine rpm sensor)
4. Camshaft flywheel (engine timing sensor)
NOTE The numerical values relating to the signals indicate the crankshaft angles in advance of TDC.
Copyright by Fiat Auto
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