There are many reasons for a car battery to drain quickly. The four most common reasons for a battery to drain quickly are below. When your battery is showing signs of quick drainage, it is a good idea to have your battery inspected or even replaced at Paul Campanella’s Auto and Tire Center.

Old Battery:

Batteries that are old, have simply been drained completely and are unable to hold a full charge. It is recommended to replace your battery every four to five years.

Parasitic Drain:

Radio presets, security alarms or clocks running after the engine is off can drain your battery. The most common causes o f a parasitic drain are under hood lights, trunk lights, headlights, or glove box lights that do not turn off when the door is closed. Relay switches that are stuck in the “on” position can also cause a battery to drain

Faulty Charging System:

A faulty charging system can also drain the battery while the car is running. If the alternator is not pushing out enough voltage, the battery will drain quickly. Once the battery drains, the headlights and radio will stop working and the car will no longer start.

Bad Alternator Diode:

A good Alternator Diode allows current to flow in one direction. However, a bad diode can leak and allow the current to flow in the opposite direction. F this happens it may keep the charging circuit on after the vehicle engine is off and will cause the battery to drain.