How Can I Test My Car Battery for a Trickle Drain?
Automobile batteries provide a grounding source for an automobile, as well as providing start-up power for the engine and ignition electronics. Typically, when an automobile is switched off, only a negligible draw of electrical current should exist. If an automobile continues to draw excessive electrical current when the engine is switched off, a parasitic drain on the battery is the problem, which must be found. Hold the positive battery terminal retaining bolt with the slip-joint pliers. Using the adjustable wrench, loosen the positive battery terminal retaining nut. Disconnect the positive battery cable from the positive battery post. Turn on the multimeter, and set it to the “DC Amps” setting. Place one of the probes on the positive battery post, and place the other probe on the battery cable terminal. Read the multimeter display; if the electrical current measurement is more than 50 mA, there is a parasitic drain on the battery. Install the battery cable on the positive battery te