Checking The Throttle Position Sensor Input Voltage; Checking The Intake Air Pressure Sensor - Yamaha YZ 2018 Series Owner's Service Manual

G/W
G/W
1
b. Immerse the coolant temperature sensor in
a container filled with coolant.
TIP
Make sure the coolant temperature sensor ter-
minals do not get wet.
c. Place a thermometer in the coolant.
d. Slowly heat the coolant, and then let it cool
to the specified temperature indicated in the
table.
e. Check the coolant temperature sensor for
continuity at the temperatures indicated in
the table.
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EASB29B364
EASB29B365
CHECKING THE THROTTLE POSITION
SENSOR INPUT VOLTAGE
1. Check:
• Throttle position sensor input voltage
Out of specification  Replace the ECU.
Throttle position sensor input
voltage
4–6 V
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a. Connect the test harness S-pressure sensor
(3P) to the throttle position sensor coupler
and the wire harness.
b. Connect the digital circuit tester (DC) to the
test harness S-pressure sensor (3P).
B/L
B/L
2
8-71
ELECTRICAL COMPONENTS
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with
tachometer
YU-A1927
Test harness S– pressure sensor
(3P)
90890-03207
Test harness S– pressure sensor
(3P)
YU-03207
• Positive tester probe 
Blue "1"
• Negative tester probe 
Black/Blue "2"
1
c. Start the engine.
d. Measure the throttle position sensor input
voltage.
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EASB29B366
CHECKING THE INTAKE AIR PRESSURE
SENSOR
1. Check:
• Intake air pressure sensor output voltage
Out of specification  Replace.
Intake air pressure sensor output
voltage
3.61–3.67 V at 101.3 kPa (3.61–
3.67 V at 1.01 kgf/cm
V at 14.7 psi)
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a. Connect the digital circuit tester (DC) to the
intake air pressure sensor coupler (wire har-
ness side).
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with
tachometer
YU-A1927
2
2
, 3.61–3.67