Crankshaftspeedsensor - BMW 5251 Service Manual

120-1
2
ignition
System
Crankshaftspeedsensor
Crankshaft speed sensor, replacing (M52, M52 TU and
M54 engines)
4
Crankshaft speed sensor for 6-cylinder engine is mounted in
the left rear side of the cylinder block below the starter (ar-
row). The sensor reads a toothed pulse wheel mounted to
the end of the crankshaft.
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if the Engine Control Module (ECM) does not receive a signal
from the crankshaft speed sensor during cranking, the en-
gine will not start.
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If the OBD II svstem misfire detection ~rotocol detects a cat-
- -
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sensor components. Ine Check Engine lignr (Malfuncrion In-
dicator Light or MIL) will be illuminated.
NOTE-
I f the crankshaft speed sensor pulse wheel is damaged, the
engine will have to be disassembled down to the crankshaft
to reolace the wheel.
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Make certain ignition has been turned off.
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Raise car and support in a safe manner.
WARNING
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Make sure the car is stable and well supported at all times.
Use a professional automotive lift orjacltstands designed for
the ouroose. A floor iaclc is not adequate support.
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Remove under engine splash guard
4
Working underneath starter:
Cut off wire tie securing crankshaft speed sensor harness
connector (arrow) to sensor.
* Disconnect harness connector.
4
Remove sensor mounting fastener (arrow) and remove sen-
sor from cylinder block.
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Installation is reverse of removal, noting the following:
Use a new O-ring when installing sensor.
Be sure wiring is routed in same orientation.
Secure sensor using new wire ties.
Use scan tool to read out and clear ECM fault memory.