Battery or Alternator Problems

A car battery stores the energy to start the vehicle, and the alternator produces the energy while the engine is running and also recharges the battery. Problems with either one of these components can keep a vehicle from moving.

Battery Plate Problems

Eventually, a battery will go dead and cannot be recharged. One reason for this is the plates inside the battery may get encrusted with sulfate, and a charge cannot pass through them. The plates may also degrade, or there will be a current leakage between the cell plates. The current leakage can cause a short circuit.

Voltage Regulator

Voltage regulators prevent the battery from overcharging by reducing the current of the electromagnet as the engine RPMs increase. This limits the alternator's output. In many cars, the voltage regulator is located inside the alternator. A malfunctioning voltage regulator requires disassembling the alternator to gain access to the voltage regulator. A poorly operating voltage regulator may go unnoticed because the charge warning lamp may not illuminate.

Poorly Charging Alternator

A poorly charging or overloaded alternator will cause the battery to wear out prematurely. Other symptoms include: the outside lights may be dim, and the charge warning lamp on the instrument panel will stay on. The engine will crank slowly as well.

References

• "Reader's Digest Complete Car Care Manual"; Robert Beason; 1981
• 2 Car Pros: How to Check a Battery
• Econofix: Alternator