Yamaha YFM7FGPW Service Manual page 434

EBS01066
3. Charging voltage
• Connect the engine tachometer to the
spark plug lead.
• Connect the pocket tester (DC 20 V) to the
battery as shown.
Positive tester probe →
positive battery terminal 1
Negative tester probe →
negative battery terminal 2
• Start the engine and let it run at approxi-
mately 1,000 r/min.
• Measure the charging voltage.
Charging voltage
14 V at 5,000 r/min
NOTE:
_
Make sure the battery is fully charged.
• Is the charging voltage within specifica-
tion?
NO
YES
The charging circuit
is OK.
9 - 29
CHARGING SYSTEM
EBS01100
4. Stator coil resistance
• Disconnect the AC magneto coupler from
the wire harness.
• Connect the pocket tester (Ω × 1) to the
stator coils.
Positive tester probe → white terminal 1
Negative tester probe → white terminal 2
Positive tester probe → white terminal 1
Negative tester probe → white terminal 3
Positive tester probe → white terminal 2
Negative tester probe → white terminal 3
• Measure the stator coil resistance.
Stator coil resistance
0.108 ~ 0.132 Ω at 20 °C (68 °F)
YES
5. Wiring
• Check the entire charging system's wiring.
Refer to "CIRCUIT DIAGRAM".
• Is the charging system's wiring properly
connected and without defects?
YES
Replace the rectifier/
regulator.
–
ELEC
W W W
1 2 3
NO
Replace the crank-
shaft position sensor/
stator assembly.
NO
Properly connect or
repair the charging
system's wiring.
+