Yamaha XV19SX(C) Service Manual page 482

ECA14390
CAUTION:
To prevent damaging the EXUP servo motor,
perform this test within a few seconds of
connecting the battery.
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EAS28410
CHECKING THE INTAKE AIR PRESSURE
SENSOR
The following procedure applies to both of the in-
take air pressure sensors.
1. Check:
• Intake air pressure sensor output voltage
Out of specification → Replace.
Intake air pressure sensor output
voltage
3.75–4.25 V
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a. Connect the pocket tester (DC 20 V) to the in-
take air pressure sensor coupler as shown.
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
• Positive tester probe →
pink/white "1" or pink/yellow
• Negative tester probe →
black/blue "2"
b. Turn the main switch to "ON".
c. Measure the intake air pressure sensor out-
put voltage.
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ET1D71016
CHECKING THE AIR TEMPERATURE
SENSOR
1. Remove:
• Air temperature sensor
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2
1
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ELECTRICAL COMPONENTS
EW1D71004
WARNING
• Handle the air temperature sensor with
special care.
• Never subject the air temperature sensor to
strong shocks. If the air temperature sen-
sor is dropped, replace it.
2. Check:
• Air temperature sensor resistance
Out of specification → Replace.
Air temperature sensor resis-
tance
290–390 Ω at 80 °C (176 °F)
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a. Connect the pocket tester (Ω × 100) to the air
temperature sensor terminals as shown.
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
3
b. Immerse the air temperature sensor "1" in a
container filled with water "2".
NOTE:
Make sure that the air temperature sensor termi-
nals do not get wet.
c. Place a thermometer "3" in the water.
d. Slowly heat the water, then let it cool down to
the specified temperature.
e. Measure the air temperature sensor resis-
tance.
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7-91
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1
2
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