Yamaha YZF-R125 Service Manual page 345

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b. Measure the throttle position sensor input
voltage.
Out of specification → Replace or repair the
wire harness.
Throttle position sensor input
voltage
5 V
c. Connect the digital circuit tester to the termi-
nals of the throttle body sensor assembly
coupler as shown.
• Positive tester probe →
yellow terminal "3"
• Negative tester probe →
gray/black terminal "2"
d. While slowly opening the throttle, check that
the throttle position sensor output voltage is
increased.
Voltage does not change or it changes
abruptly → Replace the throttle body.
Out of specification (closed position) → Re-
place the throttle body.
Throttle position sensor output
voltage (closed position)
0.63–0.73 V
Gy/R Y Gy/B
1 3
L LLL L LLL L L LLL L
Intake air pressure sensor
1. Check:
• Intake air pressure sensor output voltage
Out of specification → Replace the throttle
body.
Intake air pressure sensor output
voltage
4.70–5.20 V
M MMM M MMM M M MMM M
a. Connect the pocket tester (DC 20 V) to the
throttle body sensor assembly coupler as
shown.
2
L LLL L L LLL L L LLL L
M MMM M M MMM M M MMM M
ELECTRICAL COMPONENTS
• Positive tester probe →
pink/white "1"
• Negative tester probe →
gray/black "2"
b. Set the main switch to "ON".
c. Measure the intake air pressure sensor out-
put voltage.
L LLL L LLL L
Intake air temperature sensor
1. Check:
• Intake air temperature sensor resistance
Out of specification → Replace the throttle
body.
M MMM M MMM M
a. Connect the pocket tester (Ω × 1k) to the
throttle body sensor assembly coupler as
shown.
LLL
• Positive tester probe →
brown/white "1"
• Negative tester probe →
gray/black "2"
MMM
8-74
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
Gy/B
Gy/R Y
2 1
L LLL L L LLL L L LLL L
Intake air temperature sensor re-
sistance
5.7–6.3 kΩ
M MMM M M MMM M M MMM M
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
L LLL L LLL
M MMM M MMM