Electrical system
Checking the ignition coil
In this manual: Electrical system
~1min read
1. Check:
Primary coil resistance Out of specification
Replace.
a. Disconnect the ignition coil connectors from the ignition coil terminals.
b. Connect the pocket tester (
× 1)
to the ignition coil as shown.
Positive tester probe
red/white "1"
Negative tester probe
orange "2"

c. Measure the primary coil resistance.
2. Check:
Secondary coil resistance Out of specification
Replace.
a. Disconnect the spark plug cap from the ignition coil.
b. Connect the pocket tester (
×
1k) to the ignition coil as shown.
- Positive tester probe
orange "1" - Negative tester probe
spark plug lead "2"

c. Measure the secondary coil resistance.
Test yourself
A quick Yamaha YZF-R125 quiz: every answer comes with an explanation and a link to the manual page.
Was this page helpful?