Checking The Stator Coil; Checking The Rectifier/Regulator - Yamaha MT-09 2021 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
0.152–0.228 Ω
a. Connect the digital circuit tester to the stator
coil coupler as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with ta-
chometer
YU-A1927
• Positive tester probe
white "1"
• Negative tester probe
white "2"
• Positive tester probe
white "1"
• Negative tester probe
white "3"
• Positive tester probe
white "2"
• Negative tester probe
white "3"
b. Measure the stator coil resistance.
1 2 3
W W W
8-61
ELECTRICAL COMPONENTS
EAS30680

CHECKING THE RECTIFIER/REGULATOR

1. Check:
• Rectifier/regulator input voltage
Out of specification → Correct the stator coil
condition.
Refer to "CHECKING THE STATOR COIL"
on page 8-61.
Rectifier/regulator input voltage
above 14 V at 5000 r/min
a. Connect the digital circuit tester (AC V) to
the rectifier/regulator coupler as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with ta-
chometer
YU-A1927
• Positive tester probe
white "1"
• Negative tester probe
white "2"
• Positive tester probe
white "1"
• Negative tester probe
white "3"
• Positive tester probe
white "2"
• Negative tester probe
white "3"
b. Start the engine and let it run at approxi-
mately 5000 r/min.
c. Measure the rectifier/regulator input volt-
age.
2. Check:
• Rectifier/regulator output voltage
Out of specification → Replace the rectifier/
regulator.
1 2 3
W W W