Alternator System Testing

Many different models of test equipment are available for testing the voltage and current output of the various alternators systems. Connect and operate the equipment in accordance with the manufacturers instructions.

If voltage or current output of the complete system is below specifications, by-pass the voltage regulator and test the alternator alone. If output is still below specifications, the alternator is at fault. If the output rises to specifications when the regulator is bypassed, the regulator is at fault.

On the common regulators several methods of bypassing can be used for testing. On regulators with plug-in connectors, remove the harness from the regulator and plug a jumper adapter into the harness plug.

On Chrysler Corp. vehicles with open terminal regulators, disconnect the ignition and field wires and connect them together with a jumper lead.

On 1968 Delco-Remy alternators with integral regulators, attach a jumper wire between the regulator heat sink and the alternator frame.

On 1969 and later Delco-Remy alternators with integral regulators, insert a screwdriver into the "D" shaped test hole in the end of the alternator to ground field winding.

On Ford (Motorcraft) alternators with integral regulator, connect a jumper wire between the regulator field terminal and ground on the alternator frame.