On integral gm units. Readings range from 3 to 7 amps.

Part 2 How To Test The Alternator With A Multimeter 1994 1995 3 8l Ford Mustang

However if you simply want to check the state of charge you can do so with a.

Test charging system with multimeter. Testing your car battery s state of charge with a multimeter. If you want to check your battery s overall health you may ask a professional to do a load test using a hand held digital analyzer. A good car battery should be able to accept and hold a charge.

With alternator not turning jump terminals together and connect both to batt with digital multimeter in series set to measure 10 amps. Load unit as in figure 2 and measure field current with current clamp or use 10 a jack on digital multimeter.