Yamaha TW125 1999 Service Manual page 250

12. Diode
S Disconnect the diode from the coupler.
S Connect the pocket tester (Ω
diode terminals as shown.
S Measure the diode for continuity as follows.
Tester positive probe !
blue/white
Tester negative probe !
blue/black
Tester positive probe !
blue/black
Tester negative probe !
blue/white
NOTE:
When you switch the "–" and "+" leads of the
digital pocket tester the readings in the above
chart will be reversed.
S Are the tester readings correct?
YES
1) to the
1
Continuity
2
No continu-
1
ity
2
NO
Replace the relay
unit.
IGNITION SYSTEM
EAS00766
13. Wiring
S Check the entire ignition system's wiring.
Refer to "CIRCUIT DIAGRAM".
S Is the ignition system's wiring properly con-
nected and without defects?
NO
Properly connect or
repair the ignition
system's wiring.
7-11
ELEC
YES
Replace the CDI unit.