How Can I Test My Car Battery for a Trickle Drain?
- 1). 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.
- 2
Measure the output current with a multimeter to determine whether the battery is being drained.Digital Multimeter image by TekinT from Fotolia.com
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. - 3). Install the battery cable on the positive battery terminal, and tighten the retaining nut until the terminal is snug on the battery post. Open the automobile fuse box.
- 4). Pull the first fuse out of the fuse holder. Place one probe on one of the fuse holder connectors, and place the other probe on the opposite fuse holder connector. Read the multimeter display. If the electrical current reading is less than 50 mA, replace the fuse and repeat this step on the other fused circuits until the battery draining device is found.
Source...