Checking The Exup Servo Motor; Checking The Intake Air Pressure Sensor; Checking The Intake Air Temperature Sensor - Yamaha WR250R Service Manual

sor shaft, check that the throttle position sen-
sor voltage is within the specified range.
The voltage does not change or it changes
abruptly → Replace the throttle position sen-
sor.
Throttle position sensor output
voltage
0.6–5.0 V
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EAS28360

CHECKING THE EXUP SERVO MOTOR

1. Check:
EXUP servo motor operation
G
Out of specification → Replace.
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a. Disconnect the EXUP cables from the EXUP
servo motor pulley.
b. Disconnect the EXUP servo motor coupler
from the wire harness.
c. Connect the battery leads to the EXUP servo
motor coupler as shown.
Positive battery lead
Black/Green "1"
Negative battery lead
Black/Red "2"
1
d. Check that the EXUP servo motor pulley ro-
tates several times.
ECA14390
CAUTION:
To prevent damaging the EXUP servomotor,
perform this test within a few seconds of
connecting the battery.
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2
8-80
ELECTRICAL COMPONENTS
EAS28410
CHECKING THE INTAKE AIR PRESSURE
SENSOR
1. Check:
Intake air pressure sensor output voltage
G
Out of specification → Replace.
Intake air pressure sensor output
voltage
3.75–4.25V
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a. Connect the pocket tester (DC 20 V) to the in-
take air pressure sensor coupler (wire har-
ness side) as shown.
Digital circuit tester
90890–03174
Model 88 Multimeter with ta-
chometer
YU-A1927
Positive tester probe
Pink/White "1"
Negative tester probe
Black/Blue "2"
2
b. Set the main switch to "ON".
c. Measure the intake air pressure sensor out-
put voltage.
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EAS28420
CHECKING THE INTAKE AIR
TEMPERATURE SENSOR
1. Remove:
Intake air temperature sensor
G
(from the air filter case.)
EWA14110
WARNING
Handle the intake air temperature sensor
G
with special care.
Never subject the intake air temperature
G
1