Checking The Stator Coil; Checking The Rectifier/Regulator; Checking The Fuel Sender - Yamaha MBK MW125 2014 Service Manual

EAS30566

CHECKING THE STATOR COIL

1. Disconnect:
• Stator coil coupler
(from the wire harness)
2. Check:
• Stator coil resistance
Out of specification → Replace the stator coil.
Stator coil resistance
0.400–0.600 Ω (W - W)
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a. Connect the digital circuit tester to the stator
coil coupler as shown.
Digital circuit tester
90890-03174
Model 88 Multimeter with ta-
chometer
YU-A1927
• Positive tester probe →
white "1"
• Negative tester probe →
white "2"
1
W
W
2
b. Measure the stator coil resistance.
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EAS30680

CHECKING THE RECTIFIER/REGULATOR

1. Check:
• Charging voltage
Out of specification → Replace the rectifi-
er/regulator.
Charging voltage
14 V at 5000 r/min
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a. Connect the pocket tester (DC 20 V) to the
battery terminals as shown.
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ELECTRICAL COMPONENTS
• Positive tester probe →
positive battery terminal "1"
• Negative tester probe →
negative battery terminal "2"
▼▼▼
2
b. Start the engine and let it run at approximate-
ly 5000 r/min.
c. Measure the charging voltage.
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EAS30573

CHECKING THE FUEL SENDER

1. Remove:
• Fuel pump
(from the fuel tank)
2. Check:
• Fuel sender resistance
Out of specification → Replace the fuel pump
assembly.
Fuel sender
▲▲▲
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a. Connect the pocket tester (Ω × 10/× 100) to
the fuel sender terminals as shown.
▼▼▼
• Positive tester probe →
green "1"
• Negative tester probe →
black "2"
8-66
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
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Sender unit resistance (full)
10.0–14.0 Ω
Sender unit resistance (empty)
267.0–273.0 Ω
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Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
1
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