Schumacher SC-12000A owner manual Using the built-in alternator tester, Alternator Testing Notes

charge should be removed by temporar- ily creating a load on the battery, such as by turning on lights or other accessories. The battery % ranges from 0 to 100.

The battery tester is only designed to test batteries. Testing a device with a rapidly changing voltage could yield unexpected or inaccurate results.

using the built-in alternator tester

This battery charger has a built-in alter- nator tester that displays either an accu- rate alternator voltage or an estimate of the alternator’s relative output compared to normal alternators. The Alternator % values displayed should be taken as general reference, not precise diagnosis. The alternator tester functions the same as the battery tester (see previous sec- tion of this manual for details) with a few differences.

TESTING SEQUENCE

There are three basic steps required to use the SC-12000A as an alternator tester.

1.Connect the charger battery clamps to the battery or charging system. Be sure to follow all of the precautions listed under “OPERATING INSTRUCTIONS”.

2.Connect the charger power cord to a 120V AC 2-prong wall outlet. Again, be sure to follow all of the precautions listed under “OPERATING INSTRUCTIONS”.

3.Start the vehicle and turn on the vehicle’s headlights. Read the voltage on the digital display or press the digital display button to set the tester to Alternator % and read the alternator percent.

TESTER STATUS LEDs

When the SC-12000A is operating as an alternator tester, the status LEDs light under the following conditions.

•The Charged (green) LED will light if the output of the charging system is at the normally desired level.

•The CHARGING (yellow) LED does not light in the alternator test mode.

•The connected LED lights if a voltage is detected.

•When the tester display mode is set to voltage, the CHARGED and

CHARGING LEDs won't light (it could be testing a battery or an alternator).

ALTERNATOR TESTING NOTES

•The alternator percent display can range from 0 to 199.

•The digital display cannot be set to Alternator % during charging.

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