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

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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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Alternator: Testing and Inspection

Fig. 2 CS Current Output Specifications:





The following procedure uses a S-VAT-40 volts-amps-tester or equivalent.

1. With carbon pile knob off, turn volt selector to EXT-18 VDC.
2. Connect positive and negative load leads to respective battery terminals.
3. Connect amp probe to output lead.
4. Adjust amp meter reading to 0, then start engine and run for 15 minutes. Ensure a minimum output of 13.0 volts has been reached before testing current output.
5. Refer to alternator specifications, then set RPM and adjust carbon pile to match alternator output.
6. Battery voltage should not drop below 13.0 volts.
7. If output is not as specified, replace alternator.