Troubleshooting - Yamaha TW125 1999 Service Manual

EAS00774

TROUBLESHOOTING

The battery is not being charged.
Check:
1. fuse
2. battery
3. charging voltage
4. stator coil assembly resistance
5. wiring
(of the entire charging system)
NOTA:
S Before troubleshooting, remove the following
part(-s):
1) side covers (left and right)
2) seat
S Troubleshoot with the following special
tool(-s).
Engine tachometer
90890-03113
Pocket tester
90890-03112
EAS00738
1. Fuse
S Check the main fuses for continuity.
Refer to "CHECKING THE FUSES" in chap-
ter 3.
S Is the main fuses OK?
YES
2. Battery
S Check the condition of the battery.
Refer to "CHECKING AND CHARGING THE
BATTERY" in chapter 3.
Specific gravity
1.280 at 20_C
S Is the battery OK?
YES
NO
Replace the fuse.
NO
S Refill the battery fl-
uid.
S Clean the battery
terminals.
S Recharge or repla-
ce the battery.
CHARGING SYSTEM
EAS00775
3. Charging voltage
S Connect the engine tachometer to the spark
plug lead.
S Connect the pocket tester (DC 20 V) to the
battery as shown.
Tester positive probe !
Tester negative probe !
S Start the engine and let it run at approximate-
ly 5,000 r/min.
S Measure the charging voltage.
Charging voltage
14.5 V at 5,000 r/min
NOTE:
Make sure that the battery is fully charged.
S Is the charging voltage within specification?
NO
7-21
ELEC
battery positive terminal
battery negative terminal
The charging circuit
is OK.
YES