Electrical 101

Battery Testers

Batteries usually lose their charge slowly, they just don’t quit working. A battery tester is the best way to show the condition of a battery. A good battery tester will tell you if a battery is good, ready to fail, or needs to be replaced. The most common home devices that use batteries are remote controls, flashlights, and automobile keyless entry devices. Find Battery Testers

When a battery operated device doesn’t work properly, it is probably the battery that is failing.

Cleaning Battery Contacts

If batteries are replaced or tested as good, and the device is still not working properly, the contacts on the battery and/or battery compartment may need to be cleaned. Unseen corrosion can build up on battery contacts preventing a good connection. Using a clean pencil eraser on the contacts or just spinning the battery inside the compartment can provide a better battery connection. If you see white deposits on the compartment contacts, see What if a battery leaks?

Cleaning the front (transmitter) of a remote control and the receiver on a TV or other device can also improve performance. Dirt or grease can impede a signal from the transmitter to the receiver.

Battery Tester vs Multimeter

A good battery tester puts a small load on the battery by drawing a small current through the tester. Multimeters have a high input impedance and do not put a load on the battery. While measuring 1.6V on a 1.5V battery may indicate a good battery, measuring 1.4V does not necessarily indicate a low battery.