Yamaha YJ50RAP Service Manual page 204

EAS00776
4. Source coil resistance
• Disconnect the stator coil assembly cou-
pler from the wire harness.
• Connect the pocket tester (Ω × 1) to the
source coils as shown.
Positive tester probe → white 1
Negative tester probe → ground 2
Positive tester probe → yellow/red 3
Negative tester probe → ground 2
W/R W/L
1
W
• Measure the source coil resistances.
Stator coil resistance (W-B)
0.29 ~ 0.43 Ω at 20°C (68°F)
• Is the stator coil OK?
YES
The wiring circuit
from the main
switch to the head-
light coupler is
faulty and must be
repaired.
EAS00789
2. The meter light fails to come on.
1. Meter light bulb and socket
• Check the meter light bulb and socket for
continuity.
• Are the meter light bulb and socket OK?
YES
2
3
Y/R
NO
Replace the recti-
fier/regulator.
NO
Replace the meter
light bulb, socket or
both.
LIGHTING SYSTEM
2. Voltage
• Connect the pocket tester (20 V) to the
meter light coupler (wire harness side) as
shown.
Positive tester probe → brown 1
Negative tester probe → black 2
Meter light assembly coupler
• Set the main switch to "ON".
• Measure the voltage (12 V) of brown 1 on
the meter light coupler (wire harness side).
• Is the voltage within specification?
This circuit is OK.
EAS00790
3. The tail/brake light fails to come on.
1. Tail/brake light bulb and socket
• Check the tail/brake light bulb and socket
for continuity.
• Are the tail/brake light bulb and socket
OK?
7 - 27
ELEC
2 1
Br B B Br
Y Br/W
Br/W Y
Gy Gy
YES
The wiring circuit
from the
switch to the meter
light coupler
faulty and must be
repaired.
YES
Replace
brake light
socket or both.
– +
NO
main
is
NO
the tail/
bulb,