Yamaha YJ50RAP Service Manual page 217

TROUBLESHOOTING
The auto choke fails to operate
Check:
1. auto choke resistance
2. lighting coil resistance
3. voltage
NOTE:
@
• Before troubleshooting, remove the following
part(s):
1) center cover
• Troubleshoot with the following special
tool(s).
Pocket tester
YU-03112
1. Auto choke resistance
• Disconnect the auto choke coupler from
the wire harness.
• Connect the pocket tester (Ω × 1) to the
auto choke coupler as shown.
Tester positive probe → black 1
Tester negative probe → black 2
2
Auto choke resistance
8 ~ 12 Ω at 20 °C (68 °F)
• Is the auto choke unit OK?
YES
1
B B
NO
Replace the auto
choke.
AUTO CHOKE SYSTEM
2. Source coil resistance
• Disconnect the stator coil assembly cou-
pler from wire harness.
• Connect the pocket tester (Ω × 1) to the
source coil lead.
Tester positive probe → yellow/red 1
Tester negative probe → ground 2
Source coil resistance
0.18 ~ 0.28 Ω at 20 °C (68 °F)
7 - 40
ELEC
2
1
W/R W/L
W Y/R
YES
Replace the stator
coil assembly.
– +
NO