Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Ignition Coil: Testing and Inspection

Ignition Coil Inspection - Checking Primary Resistance:





- Disconnect ignition coil electrical connector.
- Measure resistance across primary terminals.

Should be 0.20 - 0.30 ohms


Ignition Coil Inspection - Checking Secondary Resistance:





- Remove coil high tension wire.
- Measure resistance between high voltage terminal and indicated connector terminal.

Should be 6 - 11K ohms

- Replace coil if results are not achieved.