Page 252 - Manual_Polaris_RZR_ProXP-20-21

ENGINE ELECTRICAL

KNOCK SENSOR
KNOCK SENSOR OVERVIEW KNOCK SENSOR TESTING
The knock sensor is located on the cylinder block, below 1. Disconnect the harness going to the knock sensor.
the MAG intake port.
2. Use a multimeter to ohm between the two pins on the
sensor harness.
Knock Sensor:
4,870 kΩ

3. If the sensor measures OL between the pins or there
is continuity to chassis ground, replace the knock
sensor.

KNOCK SENSOR REPLACEMENT

1. Disconnect the harness q going to the knock sensor.

The knock sensor “listens” for combustion knock by
converting internal engine noise in to an electrical signal.
The ECU uses the signal to determine the level of knock
within the combustion chambers after each combustion
event.

When the ECU determines detonation has occurred, the
CHECK ENGINE lamp will turn on.
The ECU will retard timing first and then reduce the boost
target if detonation continues.
If detonation occurs:

• Drain the fuel and fill with fresh fuel. Always use
premium fuel (91+ octane)
2. Remove the knock sensor mounting bolt w and
• Check for non-approved Polaris modifications to the remove the sensor from the cylinder.
engine or exhaust system
NOTICE
• Verify there is no water or foreign material in the fuel
The knock sensor does not run through a coolant jacket
• Verify there is no internal engine damage in the cylinder. No fluid should come out of the hole
• Verify the cooling system is working properly when the sensor is removed.

3. Install the new knock sensor. The knock sensor
NOTICE
should be orientated so the sensor lead does not rub
Install the knock sensor fastener clean and without on any component. The sensor lead should point
thread locker or oil. straight back and be retained. Torque mounting bolt
to specification.

TORQUE
Knock Sensor Mounting Bolt:
15 ft-lb (20 Nm)

4. Connect knock sensor harness.

4.6 9930583 R01 - 2020-2021 RZR PRO XP / XP 4 Service Manual
© Copyright Polaris Industries Inc.