Alternator Output Test: Mirage
- Connect ammeter and voltmeter to vehicle. See Fig 1. Connect tachometer to engine. Start engine. Turn on all electrical accessories. Start engine and increase speed to 1150 RPM. Note maximum reading on ammeter.
- If alternator output is less than 70% of rated output, crank engine or leave accessories on for 2-3 minutes to slightly discharge battery. Repeat step 1). If output is still less than 70%, alternator is defective. If output is okay, perform REGULATED VOLTAGE TEST .