Checking The Spark Plug Cap; Checking The Ignition Coil - Yamaha XG250 Service Manual

d. Check the diode for no continuity.
NOTE:
When you switch the positive and negative
tester probes, the readings in the above chart
will be reversed.
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EAS28060

CHECKING THE SPARK PLUG CAP

1. Check:
Spark plug cap resistance
●
Out of specification → Replace.
Resistance
10.0 kΩ
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a. Remove the spark plug cap from the spark
plug lead.
b. Connect the pocket tester (Ω × 1k) to the
spark plug cap as shown.
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
c. Measure the spark plug cap resistance.
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EAS28090

CHECKING THE IGNITION COIL

1. Check:
Primary coil resistance
●
Out of specification → Replace.
Primary coil resistance
0.18–0.28 Ω
ELECTRICAL COMPONENTS
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a. Disconnect the ignition coil connectors from
the ignition coil terminals.
b. Connect the pocket tester (Ω × 1) to the igni-
tion coil as shown.
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
Positive tester probe
●
Orange "1"
Negative tester probe
●
Ignition coil base "2"
2
1
c. Measure the primary coil resistance.
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2. Check:
Secondary coil resistance
●
Out of specification → Replace.
Secondary coil resistance
6.30–9.50 kΩ
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a. Disconnect the spark plug cap from the igni-
tion coil.
b. Connect the pocket tester (Ω × 1k) to the ig-
nition coil as shown.
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
Negative tester probe
●
High tension code "1"
Positive tester probe
●
Orange "2"
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