Amperage Output Test
NOTE:
Ammeter with clamp-type test lead is recommended. Perform test quickly after starting engine, as charging amperage will drop quickly.
- Disconnect battery ground cable and alternator output wire from alternator terminal "B". See Fig 1. Connect ammeter in series between terminal "B" and disconnected output wire. Connect voltmeter between terminal "B" and ground. Reconnect battery ground wire.
- Ensure voltmeter reads battery voltage. If voltmeter reads zero volts, suspect an open in wire between alternator "B" terminal and positive battery terminal, a blown fusible link or poor ground.
- Turn on all electrical accessories. Start engine and accelerate to 2500 RPM. Read maximum output amperage. If alternator amperage output is within 10 percent of rated output, alternator is functioning properly. See ALTERNATOR SPECIFICATIONS table.