Checking The Ignition Coils - Yamaha MX775 Service Manual

ELECTRICAL COMPONENTS
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e. Measure the engine temperature sensor resis-
tance.
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3.
Install:
• Engine temperature sensor

CHECKING THE IGNITION COILS

The following procedure applies to all of the ignition coils.
1.
Check:
• Primary coil resistance
Out of specification  Replace.
Primary coil resistance:
0.44–0.66 
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a. Remove the ignition coil from the spark plug.
b. Connect the digital circuit tester () to the ignition
coil as shown.
Model 88 Multimeter with tachometer:
YU-A1927
• Positive tester probe 
Red "1" (wire harness color)
• Negative tester probe 
Black "2" (wire harness color)
c. Measure the primary coil resistance.
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2.
Check:
• Secondary coil resistance
Out of specification  Replace.
Secondary coil resistance:
5.6–8.4 k
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a. Connect the digital circuit tester () to the ignition
coil as shown.
Model 88 Multimeter with tachometer:
YU-A1927
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