Checking The Resister; Checking The Radiator Fan Motor (For Jpn); Checking The Coolant Temperature Sensor - Yamaha YZ 2018 Series Owner's Service Manual

EASB29B361

CHECKING THE RESISTER

1. Disconnect:
• Resister coupler
(from the wire harness)
2. Check:
• Resister resistance
Out of specification  Replace the resister.
Resister resistance
64.6–71.4 
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a. Connect the digital circuit tester () to the
resister as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with
tachometer
YU-A1927
• Positive tester probe 
Black "1"
• Negative tester probe 
Black "2"
b. Measure the resistance of the resister.
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EASB29B362
CHECKING THE RADIATOR FAN MOTOR
(For JPN)
1. Check:
• Radiator fan motor
Faulty/rough movement  Replace.
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a. Disconnect the radiator fan motor coupler
from the wire harness.
b. Connect the battery (DC 12 V) as shown.
• Positive battery terminal 
Blue "1"
• Negative battery terminal 
Black "2"
c. Measure the radiator fan motor movement.
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EASB29B363
CHECKING THE COOLANT TEMPERATURE
SENSOR
1. Remove:
EWA
• Handle the coolant temperature sensor
• Never subject the coolant temperature
2. Check:
1
2
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a. Connect the digital circuit tester () to the
• Positive tester probe 
• Negative tester probe 
8-70
ELECTRICAL COMPONENTS
1
L
• Coolant temperature sensor
WARNING
with special care.
sensor to strong shocks. If the coolant
temperature sensor is dropped, replace it.
• Coolant temperature sensor resistance
Out of specification  Replace.
Coolant temperature sensor re-
sistance
2512–2777  at 20 °C (2512–
2777  at 68 °F)
Coolant temperature sensor re-
sistance
210–220  at 100 °C (210–220 
at 212 °F)
coolant temperature sensor.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with
tachometer
YU-A1927
Green/White "1"
Black/Blue "2"
2
B
12V