Checking The Ignition Coils; Checking The Ignition Spark Gap - Yamaha MT-09 2021 Service Manual

c. Check the relay unit (diode) for continuity.
d. Check the relay unit (diode) for no continui-
ty.
EAS30558

CHECKING THE IGNITION COILS

The following procedure applies to all of the igni-
tion coils.
1. Check:
• Primary coil resistance
Out of specification → Replace.
Primary coil resistance
1.19–1.61 Ω
a. Disconnect the ignition coil coupler from the
ignition coil.
b. Connect the digital circuit tester (Ω) to the
ignition coil as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with ta-
chometer
YU-A1927
• Positive tester probe
Ignition coil terminal "1"
• Negative tester probe
Ignition coil terminal "2"
G089046
c. Measure the primary coil resistance.
2. Check:
• Secondary coil resistance
Out of specification → Replace.
Secondary coil resistance
8.50–11.50 kΩ
a. Connect the digital circuit tester (Ω) to the
ignition coil as shown.
1
2
8-59
ELECTRICAL COMPONENTS
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with ta-
chometer
YU-A1927
• Negative tester probe
Ignition coil terminal "1"
• Positive tester probe
Spark plug terminal "2"
2
b. Measure the secondary coil resistance.
EAS30556

CHECKING THE IGNITION SPARK GAP

1. Check:
• Ignition spark gap
Out of specification → Perform the ignition
system troubleshooting, starting with step (5).
Refer to "TROUBLESHOOTING" on page 8-
6.
Minimum ignition spark gap
6.0 mm (0.24 in)
TIP
If the ignition spark gap is within specification,
the ignition system circuit is operating normally.
a. Remove the ignition coil from the spark
plug.
b. Connect the ignition checker "1" as shown.
Ignition checker
90890-06754
Oppama pet–4000 spark checker
YM-34487
1
G089047