Battery leakage test
Battery terminal test
Battery voltage test
Cell voltage test
Battery drain test
Battery load test (battery capacity test)
Quick charge test

BATTERY LEAKAGE TEST.- A battery leakage test will determine if current is discharging across the top of the battery. A dirty battery can discharge when not in use. This condition shortens battery life and causes starting problems.

To perform a battery leakage test, set a voltmeter on a low setting. Touch the probes on the battery, as shown in figure 2-6. If any current is registered on the voltmeter, the top of the battery needs to be cleaned.

BATTERY TERMINAL TEST.- The battery terminal test quickly checks for poor electrical connection between the terminals and the battery cables. A voltmeter is used to measure voltage drop across terminals and cables.

To perform a battery terminal test (fig. 2-7), connect the negative voltmeter lead to the battery cable end. Touch the positive lead to the battery terminal. With the ignition or injection system disabled so that the engine will not start, crank the engine while watching the voltmeter reading.

Figure 2-6.- Battery leakage test.

Figure 2-7.- Battery terminal test.

If the voltmeter reading is .5 volts or above, there is high resistance at the battery cable connection. This indicates that the battery connections need to be cleaned. A good, clean battery will have less than a .5 volt drop.

BATTERY VOLTAGE TEST.- The battery voltage test is done by measuring total battery voltage with an accurate voltmeter or a special battery tester (fig. 2-8). This test determines the general state of charge and battery condition quickly.

The battery voltage test is used on maintenance-free batteries because these batteries do not have caps that can be removed for testing with a hydrometer. To perform this test, connect the voltmeter or battery tester across the battery terminals. Turn on the vehicle headlights or heater blower to provide a light load. Now read the meter or tester. A well-charged battery should have over 12 volts. If the meter reads approximately 11.5 volts, the battery is not charged adequately, or it may be defective.