Crankshaft Position Sensor; Description; Operation; Removal - Mercedes-Benz 2005 Sprinter Service Manual

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14 - 20
FUEL INJECTION
CRANKSHAFT POSITION
SENSOR

DESCRIPTION

The crankshaft position sensor is located opposite
the teeth on the flywheel and uses a non contact
method to record the position of the crankshaft. The
leading edges of each tooth on the flywheel generate
a positive signal in the position sensor, while the
trailing edges generate a negative signal. When the
crankshaft is rotating, an alternating voltage is pro-
duced as a result.
The period of the signal is the time required by the
crankshaft to turn through the gap between two fly-
wheel teeth. The clearance between the crankshaft
position sensor and the teeth of the flywheel is fixed
by the installation.
Two teeth on the flywheel are missing. The result-
ing signal gap is used by the ECM to detect the TDC
position of cylinder number one.

OPERATION

The clearance between the crankshaft position sen-
sor and the flywheel are fixed by the installation
position. Two teeth on the flywheel are missing. The
resulting gap is used by the ECM to detect DTC of
cylinder number one. The crankshaft position is cal-
culated to an accuracy of a fraction of a degree so
that the start and end of injection can occur at
exactly the right moment. The engine speed signal is
also processed by the ECM from the crankshaft sen-
sor. This signal is then transferred to other control
modules over the CAN bus.
If the crankshaft position sensor fails, the signal
that provides reference rotation is missing. Injection
may occur at the wrong time and damage the engine.
In this case, the ECM will stop triggering the injec-
tors, the engine would cut out, the engine warning
light would illuminate and the engine will not
restart.

REMOVAL

(1) Disconnect the negative battery cable.
(2) Unplug the crankshaft wiring harness connec-
tor.
(3) Remove the crankshaft sensor retaining bolt
and remove sensor (Fig. 6).

INSTALLATION

(1) Position the crankshaft position sensor into the
access hole and install retaining bolt.
Fig. 6 CRANKSHAFT POSITION SENSOR
1 - ENGINE BLOCK
2 - WIRING HARNESS CONNECTOR

3 - CRANKSHAFT POSITION SENSOR

4 - STARTER SOLENOID
(2) Tighten the retaining bolt to 80 lbs. in. (9 N·m)
(Fig. 6).
(3) Connect crankshaft position sensor wiring har-
ness connector (Fig. 6).
(4) Connect negative battery cable.

FUEL INJECTOR

DESCRIPTION
FUEL INJECTOR
There are individual fuel injectors for all five cyl-
inders. These fuel injectors are used to spray fuel
into the combustion chamber (Fig. 7).
OPERATION
The injector operation can be subdivided into four
operating states with the engine running and the
high-pressure pump generating pressure:
• Injector closed (with high pressure applied)
• Injector opens (start of injection)
• Injector opened fully
• Injector closes (end of injection)
VA

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