Checking The Pickup Coil; Checking The Source Coil - Yamaha YZ125 2022 Owner's Service Manual

c. Measure the primary coil resistance.
2. Check:
• Secondary coil resistance
Out of specification  Replace.
Secondary coil resistance
5.68–8.52 k
a. Connect the digital circuit tester () to the
ignition coil as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with tachom-
eter
YU-A1927
• Positive tester probe 
High tension cord "1"
• Negative tester probe 
Yellow "2"
b. Measure the secondary coil resistance.
EAM30583

CHECKING THE PICKUP COIL

1. Disconnect:
• Pickup coil coupler
(from the wire harness)
2. Check:
• Pickup coil resistance
Out of specification  Replace.
Pickup coil resistance
248.0–372.0 
ELECTRICAL COMPONENTS
a. Connect the digital circuit tester () to the
pickup coil coupler as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with tachom-
eter
YU-A1927
• Positive tester probe 
White/Red "1"
• Negative tester probe 
White/Blue "2"
b. Measure the pickup coil resistance.
EAM30584

CHECKING THE SOURCE COIL

1. Disconnect:
• CDI magneto coupler
(from the wire harness)
2. Check:
• Charging coil 1 resistance
(B/R–B)
Out of specification  Replace the CDI mag-
neto.
Charging coil 1 resistance
720.0–1080.0 
a. Connect the digital circuit tester () to the
CDI magneto coupler as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with tachom-
eter
YU-A1927
• Positive tester probe 
Black/Red "1"
• Negative tester probe 
Black "2"
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