Engine Protection Features; Engine Temperature Protection Modes; Engine Overheating Troubleshooting - Polaris 850 MATRYX INDY XC 129 2021 Manual

ENGINE PROTECTION FEATURES

ENGINE TEMPERATURE PROTECTION MODES

The ECU will illuminate the instrument cluster engine hot LED when it determines the engine is overheating. The ECU
will flash the TEMP. LED and shut-off the engine if it determines continued engine operation will cause serious engine
damage. The ECU makes this determination based on current engine coolant temp, engine RPM, and throttle position.
MODEL
Hot Lamp ON
650 / 850 Models
Hot Lamp FLASH
* = Only minimum (idle) and maximum (WOT) parameters listed
The driver must take immediate action to cool the engine once the hot LED is illuminated. Drive the snowmobile in
loose, unpacked snow to cool the engine. If trail conditions are poor, turn the engine off and allow it to cool.
When the engine is cool, check the coolant level in the surge bottle (reservoir). Only add coolant when the engine is
sufficiently cooled. Never add coolant when engine is hot.
If the snowmobile must be operated while the indicator LED is illuminated, drive slowly and stop the engine frequently
to allow it to cool down.
Continued engine operation with the engine hot LED illuminated may cause serious engine damage. If the ECU
determines serious engine damage may occur, the hot lamp will flash and the engine will be shut-down.
The ECU will also register and accumulate (count the number of occurrences) DTCs (110/0 or 110/16) if the engine
overheats or goes into the overheat power reduction or shut-off mode.

ENGINE OVERHEATING TROUBLESHOOTING

POSSIBLE CAUSE
Riding in poor conditions
Low coolant level
Incorrect coolant/mix ratio
Air in cooling system
Heat exchangers/hoses damaged or plugged
Thermostat malfunctioning
Water pump malfunctioning
Cylinder base gaskets / O-rings damaged
Snow flap damaged or removed
Vehicle use
Track condition/tension
9850064 R03 - 2021 650 / 850 Matryx Trail Performance / Crossover Snowmobile Service Manual
© Copyright Polaris Inc.
HOT LAMP THRESHOLD
Hot Lamp Illuminates
Idle = 201 °F (94 °C)
WOT = 185 °F (85 °C)
Hot Lamp Flashes
Engine Shuts Off
Idle = 215.6 °F (102 °C)
WOT = 201 °F (94 °C)
EV forced to closed position at 203 °F (95 °C)
SOLUTION
Ride snowmobile on good snow (loose, fresh, unpacked
snow)
Allow engine to cool. Refill coolant surge bottle to COLD
line
Verify correct coolant mixture is used
Bleed cooling system
Inspect components for damage, hose kinks, etc.
Inspect thermostat for proper operation
Inspect coolant flow
Pressure test cooling system. Verify system holds
pressure/pressure does not leak into cylinders
Inspect rear snow flap assembly. Verify flap(s) are not
damaged or missing
Verify vehicle is not overloaded during operation (high
load/high engine RPM and low ground speed)
Verify track is not missing lugs. Set correct track tension
ENGINE ELECTRICAL
4.3
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