Checking The Spark Plug Caps; Checking The Ignition Coil - Yamaha TMAX 2020 Service Manual

A
2
1
4
3
6
5
D
8
7
A. Diode 1
B. Diode 2
C. Diode 3
D. Diode 4
a. Disconnect the diode from the wire har-
ness.
b. Connect the digital circuit tester () to the
diode terminals as shown.
c. Check the diode for continuity.
d. Check the diode for no continuity.
Br
G/R
L/W
L/Y
R/B
R/W
B/W
Sb
G/Y
ELECTRICAL COMPONENTS
TIP
When you switch the positive and negative tes-
ter probes, the readings in the above chart will
be reversed.
EAS30557

CHECKING THE SPARK PLUG CAPS

The following procedure applies to all of the
spark plug caps.
1. Check:
• Spark plug cap resistance
Out of specification  Replace.
Resistance
7.50–12.50 k
a. Remove the spark plug cap from the spark
plug lead.
b. Connect the digital circuit tester () to the
spark plug cap as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with ta-
chometer
YU-A1927
c. Measure the spark plug cap resistance.
EAS30558

CHECKING THE IGNITION COIL

1. Check:
• Primary coil resistance
Out of specification  Replace.
Primary coil resistance
1.87–2.53 
a. Disconnect the ignition coil connectors from
the ignition coil terminals.
b. Connect the digital circuit tester () to the
ignition coil as shown.
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