I hadn’t driven my car in for while, and the other day I went to take it for a ride, and the battery is dead. Why?

This can be caused by a few different scenarios.First, if your car consistently sits for a long amount time and the battery is older, the battery may be sulfated to the point that it will no longer hold a charge for any significant length of time.  The new gel-cell batteries have a very high tolerance against this scenario and are a perfect solution for those of us here in the northern states where our cars get stored for long lengths of time over the winter months.  If your car has a digital radio or fuel injection and the car gets parked for a long length of time, this can actually be likely and proper occurrence.  Most new cars manufacturers actually address this exact scenario in their owner’s manual.  The computers in these types of items have a constant draw on them that, after a given length of time, will actually drain the battery.  Some new cars can actually drain a new battery in a matter of weeks.  The third scenario is that you have a constant draw (other than an expected one as outlined above) that drains the battery rather quickly.  An appliance of some type that is faulty can generally cause this problem.

Solution: The first thing to determine is what your specific problem is.  We do this by first giving the battery a good, slow, low amperage charge.  Try to avoid a quick charge as this can actually damage the battery in some instances.  Once the battery is fully charged and is up to about 14 – 14.6 volts, do a “load test” on the battery.  If the voltage drops below 10 volts or so, there is a good chance that the battery has outlived its useful life expectancy.  Likewise, if after doing the load test, the “at rest” voltage is significantly below the 14 – 14.6 that was observed prior to doing the test, there is a good chance that the battery is also bad.  If the battery is still good, we need to find out where the draw is coming from.  The way to accomplish this is by taking the negative cable off of the battery and hooking up a test light in series between the negative cable and the negative post on the battery.  Once that is set up, begin removing one fuse at a time until your test light goes out.  Once that happens, you have found the circuit where the problem exists.  In some very rare instances, the removal of every fuse will not turn the test light out.  When that happens, you’ll need to start unplugging any un-fused battery connections such as the horn relay or alternator.  In very rare instances, one of these 2 methods may not help you to locate your draw.  When that situation arises, it is recommended that you consult your harness manufacturer.