A Battery Bug is a 2-inch-square...
A Battery Bug is a 2-inch-square instrument meant to be mounted on or by the battery, although we would like one on the dash in some of our vehicles. Its LCD display shows battery voltage, which is useful in itself, but it's primarily the projected life of the battery being displayed that makes the 'Bug quite useful. This one (PN BB-SBM12) is for regular starting batteries and there is another version for deep cycle, RV, and HD applications.
It's no secret that batteries are one of the more neglected parts of our vehicles, and perhaps this is partially due to the fact that they don't communicate much with us. There's no squeaking, whining, or grinding emitting from the cells when they're unhappy. Nor is a battery able to show that it's flat the way a tire can.
Generally, one day the battery just won't start the vehicle like it's supposed to and it will be declared useless shortly thereafter. But batteries seldom drop dead completely unannounced. Sure, its performance will degrade over time, and that's to be expected, so most would simply begin thinking about replacing the battery at some point in the future once it started showing its age. Now, wouldn't it be really nice to know when that point will be-before sitting there with an engine that won't crank over and start? Yes, it would, and that's exactly what the Battery Bug is made for.
Argus Analyzers, the makers of the 'Bug, calls it a "battery failure warning system," which is a most accurate description. This device will tell how content (or unhappy) your battery is-it has now been given a means of communicating with you-if you're only willing to look at the display or listen to the warning signals the Battery Bug emits. Installation is as simple as hooking up the positive and negative leads to the battery, after which the 'Bug will show the battery voltage. Then, after starting the engine, it'll also show what the unit figures is the remaining life of the battery. Additionally, if the battery life (cranking health, in Battery Bug speak) is deemed to be below 10 percent, an audible alarm will go off and an indicator will show that it's time for a replacement. Also, a low-voltage alarm goes off when the battery falls below 11.9 volts, letting you know that it needs to be charged, and there's an overcharge warning should too much voltage be applied to the battery.
So far so good, but how does this Battery Bug get along with a winch, which often puts far more strain on the battery than a starter motor ever would? Predictably, since the 'Bug thinks that it's testing the battery during a regular start, it misinterprets the resulting draw of a winching operation, but simply resetting it by briefly unhooking one of its wires undoes any "false" readings. On the other hand, that reading can be even more useful than one from just starting the engine.
Is the Battery Bug just another gadget we can do without? Well, we could certainly keep relying on voltmeters, experience, and guesswork, but for under $40, the Battery Bug is indeed a useful tool, letting us see at a glance what the charging system is doing and which of our old batteries are still usable. Get yours at NAPA or through Amazon.com.
In one case we had just installed a "new" Optima blue-top in a vehicle, wired in the Battery Bug, and saw a 12.6-volt reading. Not particularly surprising since that battery was recently charged. However, after starting the engine, the 'Bug indicated that there was 59 percent left of that battery's life-not too shabby for a battery that had seen about eight years of use in another vehicle. More importantly, we now knew that this particular battery wouldn't leave us stranded any time soon. Here the display happens to show the battery voltage, but it constantly switches back and forth between the percentage of life left and the real-time voltage reading, with the "gauge" above showing both