What To Do If The Car Battery Isn't Charging

While you're driving, the dashboard's battery charging light ("idiot light") goes on. Or, if your car has gauges, you notice that the charge indicator is pointing to the zero mark or somewhere in the gauge's discharging zone.

Whether indicated by a warning light or gauge, one thing is certain (discounting the possibility of a faulty warning or an electrical short circuit): the car's battery is no longer being charged by the alternator or generator. Worse, depending on what electricity-using accessories you are using, headlights, air conditioner, heater, radio, stereo, and the like, the battery is discharging. And, if you're driving after dark with the headlights on, it may be happening rapidly. Headlights generally use more of the battery's energy than any other single power-using accessory, ot

Provided you immediately heed the dashboard's no charge or discharge warning, your battery is in good condition, and you take steps to minimize the amount of current drawn from the battery's ever-dwindling reservoir of electricity, there's no need to panic. If a battery is fully or nearly fully charged when the no charge or discharge signal comes on, it will still provide up to twenty-five minutes of power. That is usually enough power to operate the power-using accessories necessary to get you to a garage or mechanic.

What To Do

1. Pull to the shoulder or curb when you safely can.

2. Don't turn off the engine. Leave the engine running in Neutral or Park to avoid a potential battery-draining restart attempt. Methodically turn off every power-using accessory. (At night, you'll have to leave on your hazard lights.) If the dashboard is lighted, dim or turn off even its minimal electric lights.

3. Once you've reduced power needs, sit back for a moment and plan your next move. Should you get out, lift the hood, and attempt to find the problem, assuming it's as obvious as a busted alternator or generator belt or an equally obvious worn and shorted battery cable? The decision is yours. Car buffs would probably opt to look under the hood. You can generally correct minor battery or cable problems quickly: brushing clean corroded battery clamps or tightening them with an adjustable wrench; wrapping an obvious worn spot in the battery cables' insulation with a strip of rag or with duct tape.

But most drivers with no particular mechanical bent or curiosity will probably, and perhaps wisely, decide merely to get off the road and to a mechanic as soon as possible. Although the battery isn't being recharged, it may still have enough energy to fire the spark plugs, thus keeping the engine running. The plain fact is there normally isn't much you can do roadside to quick-fix a no-charge battery problem. The sawiest strategy is to drive on to the nearest garage or filling station, while nursing, using as few battery-energized devices as possible, your ebbing power reserve.