What is a parasitic drain?

A flat car battery can lead to a lot of inconveniences when need to use your car. A flat battery is not always caused by lights being left on. In fact, there are a lot of things that can cause the battery to drain when the car is not in use.

A parasitic battery drain is when an abnormal and continuous discharge of power occurs after your car has been turned off. This is often caused by a short circuit or an electrical device such as a radio that remains “on” even though the car is off. Parasitic battery drains can lead to your car battery going flat overnight, or when the car is left without starting for a few days or weeks.

How to diagnose a parasitic drain >

Common causes of car battery drain:

  • Electrical problems with stereo and aftermarket accessories – If a component such as a car stereo has been incorrectly installed, or set to remain on when the car is off, it will drain the battery. Sometimes, cars can lack the correct wiring to install an aftermarket head unit. This can mean that the alternative wiring solution requires the head unit to be turned off whenever the car is turned off.
  • Defective alternator diode – The alternator is responsible for charging your battery as you drive. If one of your alternator’s diodes fails, it can cause your car’s battery to drain.
    Alternator diode repairs in Hamilton >
  • Old / defective battery – Over time, your car’s battery will lose its ability to hold a charge as effectively. Since your car’s clock and alarm continue to use small amounts of power when the car is off, they can potentially drain an old battery of power. For this reason, many drivers will disconnect their batteries from the terminals if they won’t be driving for a long period of time.
    Car battery replacement in Hamilton >
  • Car lights left on – If a light is left on, it can drain your car’s battery overnight. Be sure to check that your interior lights are all turned off when exiting your car. This includes lights inside the glovebox, above your car’s sun visor mirrors and lights that switch on/off according to whether your car doors are open/shut.


Car Battery Parasitic Drain Diagnostics & Repairs in Hamilton

Is your car’s battery constantly going flat? If so, we can help!

At Grimmer Motors, our friendly, helpful mechanics can quickly and easily diagnose the cause of a car battery that isn’t holding its charge or is being drained. Whether it’s faulty wiring, an old battery in need of replacement or incorrect installation of an accessory, our team can provide a solution you can count on.

For car battery diagnostics, servicing and replacement in Hamilton, contact Grimmer Motors today!


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