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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Test 5-Charging Circuit Voltage Drop


Fig. 3 Charging Circuit Voltage Drop Test:






1. Reconnect +D lead to alternator terminal.
2. Connect a voltmeter between battery positive terminal and alternator +D terminal. Fig. 3.
3. Switch on all loads except wipers, then start engine and run at charging speed.
4. Correct voltmeter reading is not more than 0.5 volts.
5. If reading is more than specified, check for loose or dirty connection between alternator and battery.