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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Primary Input Test

Fig. 1 Primary input test:






1. Using a suitable voltmeter, connect voltmeter between coil positive terminal (B+) and ground, Fig. 1.
2. Turn ignition switch to ON position.
3. With ignition switch turned to ON position, voltmeter should indicate 12 volts (battery voltage).
4. If 12 volts is not obtained, check for faulty battery, ignition switch, wiring or electrical connections.