
9928487 R01 - 2018 RANGER XP 1000 Service Manual
© Copyright Polaris Industries Inc.
4.31
CRANKSHAFT POSITION SENSOR (CPS)
CPS OPERATION OVERVIEW
Mounted on top of the stator cover, the crankshaft
position
sensor
is
essential
to
engine
operation,
constantly monitoring the rotational speed (RPM) and
position of the crankshaft.
A ferromagnetic 35-tooth encoder ring with a missing
tooth is built onto the flywheel. The inductive speed
sensor is mounted 1.0 ± 0.26 mm (0.059 ± 0.010 in.)
away from the encoder ring. During rotation, an AC pulse
is created within the sensor for each passing tooth. The
ECU calculates engine speed from the time interval
between the consecutive pulses.
The encoder ring missing tooth creates an “interrupt”
input
signal,
corresponding
to
specific
crankshaft
position. This signal serves as a reference for the control
of ignition timing by the ECU. Synchronization of the
CPS and crankshaft position takes place during the first
two revolutions each time the engine is started. This
sensor must be properly connected at all times. If the
sensor fails or becomes disconnected for any reason, the
engine will stop running.
CPS TEST
The CPS is a sealed, non-serviceable assembly. If fault
code diagnosis indicates a problem with this sensor, test
as follows:
1. Locate the CPS harness connector
q
above the shift
cable on the right side of the vehicle and disconnect
the harness.
2. Connect
an
ohmmeter
between
the
CPS
pin
terminals shown below. A resistance value of
1000 Ω
± 10%
at room temperature should be obtained.
CPS Resistance Specification:
1000 Ω ± 10%
3. If the resistance is correct:
• Test the main harness circuit between the sensor
connector terminals and the corresponding pin
terminals at the ECU (see wiring diagram).
• Check the sensor mounting, air gap, flywheel
encoder ring for damage or runout, and flywheel
key. Inspect CPS and flywheel encoder ring for
damage. Refer to
CPS REPLACEMENT
procedure.
4. If the resistance is incorrect, follow the
CPS
REPLACEMENT
procedure.