Alternator Test

CIRCUIT GENERATORS, you must disconnect the field circuit lead at the regulator and momentarily touch this lead to the regulator BATTERY terminal. Remember, alternators do not require polarization. Various instruments can be used to locate problems in the charging system. The following sections describe troubleshooting carried out with the voltampere tester (fig. 4-8). ALTERNATOR TEST An alternator output test is one of the first tests to be made with the voltampere tester. To conduct this test, perform the following: disconnect the field wire at the alternator, and connect the field lead of the tester (fig. 4-9) to the field terminal of the alternator. Make sure the proper connector for the alternator being tested is used. Figure 4-8.-Voltampere tests. Figure 4-9.-Alternator output test. CAUTION Do NOT allow the vehicle field wire to contact ground. Start the engine and bring the rpms up to the manufacturer’s specifications. While observing the AMMETER scale for the highest current indication, adjust the load increase knob. The field activation switch will be held in the test position during this procedure. If the ammeter indication reads at the normal output (+ or -) 10 percent, the regulator must be replaced. When the ammeter indication reads at low or no output, the alternator must be repaired or replaced. GENERATOR TEST When a vehicle is equipped with an A type of field circuit generator, you may conduct a generator test by disconnecting the field at the generator and 4-5