Operation CHARM: Car repair manuals for everyone.

Alternator No-Load Test



Voltmeter:





1. Turn off all lamps and electrical components.
2. Place the transmission in park or neutral and apply the parking brake.
3. Make sure the battery is fully charged.
4. Connect a tachometer to the engine.
5. Start the engine and increase speed to approximately 1500 rpm. With no other electrical load (foot off brake pedal and doors closed), the voltmeter pointer should move upward (increase), but not more than 2 volts above the base voltage
6. Perform the Load Test. Load Test