System Output Test
- Turn ignition switch to OFF position. Disconnect negative battery cable. Disconnect generator output wire from terminal "B". See Fig 1
. Using an ammeter, connect positive ammeter lead to terminal "B" and negative lead to disconnected generator output wire.
- Using a voltmeter, connect positive voltmeter lead to generator terminal "B" and negative lead to ground. Connect negative battery cable. Start engine. Turn headlights on high beam and heater switch to HIGH position. Using a screwdriver, ground generator terminal "F". Increase engine speed to 2000 RPM and note maximum current output on ammeter.
- If maximum current output is within 10 amps of rated amp output (55 amps) and voltmeter reading is 13.5-16.0 volts, generator is okay. If maximum current output is not within 10 amps of rated amp output and/or voltmeter reading is less than 13.5 volts, repair or replace generator.
Courtesy of GENERAL MOTORS CORP.