Checking The Throttle Position Sensor Input Voltage - Yamaha YZ450F Owner's Service Manual

2. Check:
• Throttle position sensor maximum resis-
tance
Out of specification  Replace.
Resistance
6.30 k
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a. Connect the pocket tester (  1k) to the
throttle position sensor.
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
• Positive tester probe 
Blue "1"
• Negative tester probe 
Black/Blue "2"
b. Check the throttle position sensor maximum
resistance.
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3. Install:
• Throttle position sensor
TIP
When mounting the throttle position sensor, ad-
just its angle properly. Refer to "ADJUSTING
THE THROTTLE POSITION SENSOR" on
page 7-9.
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ELECTRICAL COMPONENTS
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 pocket tester (20 VDC) to the
test harness S-pressure sensor (3P).
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
Test harness S-pressure sensor
(3P)
90890-03207
YU-03207
• Positive tester probe 
Blue "1"
• Negative tester probe 
Black/Blue "2"
c. Start the engine.
d. Measure the throttle position sensor input
voltage.
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