Polaris 2005 Sportsman MV7, Service Manual

Page: 272 / 312

ELECTRICAL
10.16
FAN CONTROL CIRCUIT
OPERATION
A thermistor is located on the cylinder head. supplies
a resistance reading to the Sure Power box via the
Yellow/Black wires when the ignition key is ON. When
the thermistor reaches the specified temperature
(resistance), the circuitry contained in the Sure Power
box allows current to flow to the fan motor through to
the Orange/Black wire. The ground path for the fan
motor is through the Brown harness wire.
CAUTION: Keep hands away from fan blades.
Serious personal injury could result.
NOTE: The thermistor may not function or operation
may be delayed if coolant level is low or if air is trapped
in the cooling system. Be sure cooling system is full and
purged of air. Refer to Maintenance Chapter 2 for
cooling system information.
FAN CONTROL CIRCUIT
OPERATION / TESTING
The fan is controlled through the ECM and thermistor.
Refer to “Engine Temperature Controller” on Page
10.5 for fan operation information. Also refer to
“COOLANT TEMPERATURE SENSOR
(THERMISTOR) TEST” for Fan ON and Fan OFF
readings on the previous page.
FAN MOTOR CURRENT DRAW
A current draw test will provide a good indication of fan
motor condition. A worn or damaged fan motor will
draw more current, which causes a reduction in blade
speed and reduced cooling.
Fan Motor
Connect ammeter
to Or/Blk in series
Or/Blk
Brn
Or/Blk
1. Disconnect the harness from the fan motor.
2. Connect a DC ammeter in between the fan switch
harness wires as shown.
3. Verify fan is free to rotate. Turn ignition key and
engine stop switch to “ON” position. Read the
current draw on ammeter with fan running.
4. If the fan motor draws more than 8.8 Amps,
replace the motor.
Fan Motor Current Draw:
Less Than 15 Amps