Yamaha MX825 - Checking the Ignition Coils

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ELECTRICAL
ELECTRICAL COMPONENTS
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.
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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.
c. Measure the primary coil resistance.
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2. Check:
• Secondary coil resistance
Out of specification  Replace.
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a. Connect the digital circuit tester () to the ignition
coil as shown.
Primary coil resistance:
0.44–0.66 
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Model 88 Multimeter with tachometer:
YU-A1927
• Positive tester probe 
Red “1” (wire harness color)
• Negative tester probe 
Black “2” (wire harness color)
Secondary coil resistance:
5.6–8.4 k
Model 88 Multimeter with tachometer:
YU-A1927