Yamaha MM700A Manual page 49

TROUBLESHOOTING
Ignition coils
A
(PRIMARY CIRCUIT)
Ignition Component Resistance Test
Use an accurate ohmmeter to perform the following
tests. When switching between ohmmeter scales, always
cross the test leads and zero the needle to ensure a correct
reading.
NOTE
Resistance specifications for the ignition
components are based on measurements
values will vary according to ambient tem-
perature and temperature o f the component
tested.
PRIMARY COIL TEST
(SECONDARY CIRCUIT)
Ignition high-tension coil
1. Open the shroud and locate the ignition high tension
coils on the airbox. Refer to Figure 6 for typical coil in-
stallation.
2. Disconnect the two primary connectors from the high
tension coil.
Cheek ignition coil primary resistance as follows:
3.
a. If necessary, switch the ohmmeter to the R
scale.
nals using an accurate ohmmeter. Refer to Figure 7.
Compare the measured resistance with the specifi-
cations listed in Table 1.
d. Disconnect the meter leads.
4. Check ignition coil secondary resistance as follows:
a. Remove the spark plug cap from the end of each
high-tension cable.
scale.
e. Measure the resistance between the end of the
high-tension (spark plug) cable and the primary
lead. Refer to Figure 8.
cations listed in Table 1.
e. Disconnect the meter leads.
5. Cheek ignition coil insulation as follows:
a. If necessary, switch the ohmmeter to the R
scale.
nals and the ignition coil core (mounting). The me-
ter should read infinity.
6. If resistance tests of the coil are not as specified in
Steps 3-5, the coil is probably faulty. Have a dealership re-
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