Yamaha YZ250 Owner's Service Manual page 510

IGNITION SYSTEM
EC626003
IGNITION COIL INSPECTION
1. Inspect:
9 Primary coil resistance
Out of specification ¡ Replace.
Tester (+) lead ¡ Yellow lead 1
Tester (–) lead ¡ Black lead 2
Primary coil
resistance
0.20~0.30Ω at
20°C (68°F)
2. Inspect:
9 Secondary coil resistance
Out of specification ¡ Replace.
Tester (+) lead ¡ Spark plug lead 1
Tester (–) lead ¡ Yellow lead 2
Secondary coil
resistance
9.5~14.3kΩ at
20°C (68°F)
NOTE:
9Remove the spark plug cap by turning it coun-
terclockwise and inspect.
9Install the spark plug cap by turning it clock-
wise until it is tight.
6-4
ELEC
Tester selector
position
Ω × 1
Tester selector
position
kΩ × 1