Schumacher SWI-1555A Using the Battery Voltage Tester, Volt Battery Reading Battery Condition

Using the Battery Voltage Tester

1.With the charger unplugged from the AC outlet, connect the charger to the battery following the instructions given in sections 6 and 7.

2.Plug the charger AC power cord into the AC outlet, following the instructions given in section 8.

3.Place the Function switch in the down position.

4.Make sure the LED on the timer is next to the OFF (O) position.

5.Read the voltage on the digital display or press the Display Mode button to set the tester to BATTERY % to read the voltage as a percent of charge. Compare the voltage reading to the chart below.

12 Volt Battery Reading	Battery Condition
12.8 or More	Charged
12.2 to 12.7	Needs Charging
Less than 12.2	Discharged

Tester and Charger: When first turned on, the unit operates only as a tester, not as

a charger. To continue to use it only as a tester, avoid pressing the AUTO			button
or the TIMER button	. Selecting a time or pressing the AUTO	activates the

battery charger and deactivates the tester.

Testing After Charging: To change the battery charger back to a tester, press the Timer

button until the LED next to the OFF position is lit. Then press the Display button until the VOLTS LED is lit.

Using the Alternator Performance Tester

1.With the charger unplugged from the AC outlet, connect the charger to the battery following the instructions given in sections 6 and 7.

2.Plug the charger AC power cord into the AC outlet, following the instructions given in section 8.

3.Place the Function switch in the down position.

4.Make sure the LED on the timer is next to the OFF (O) position.

5.Start the vehicle and turn on the vehicle’s headlights. Read the voltage on the digital display. Compare the voltage reading to the chart below.

12 Volt Alternator Reading	Alternator Condition
14.6 or More	Have it checked
13.5 to 14.5	Working
Less than 13.4	Have it checked

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