Yamaha YZ125/LC Manuel D'atelier Du Proprietaire page 492

EC620000
IGNITION SYSTEM
EC621003
INSPECTION STEPS
Use the following steps for checking the possibility of the malfunctioning engine being attributable to
ignition system failure and for checking the spark plug which will not spark.
Spark gap test
No Spark
Check entire ignition
system for connection.
OK
Check "ENGINE STOP"
button.
OK
Check ignition coil.
OK
Check spark plug cap.
OK
Check CDI magneto.
OK
Replace CDI unit.
*marked: Only when the ignition checker is used.
NOTE:
9 Remove the following parts before inspection.
1) Seat
2) Fuel tank
9 Use the following special tools in this inspection.
Dynamic spark tester:
YM-34487
Ignition checker:
90890-06754
IGNITION SYSTEM
Spark
No good
No good
Primary coil
Secondary coil
No good
Pick-up coil
Source coil
6-2
ELEC
*Clean or replace
spark plug.
Repair or replace.
No good
No good
No good
No good
Pocket tester:
YU-3112-C/90890-03112
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.