Ask The Beaverton Car Guy: What’s wrong with my car battery?

By Larry “The Car Guy“ Ferguson

Hello loyal Beaverton Readers!

Over the last couple of months, I have received calls and emails about car battery failure. Usually when a vehicle will not start it is due to human error, such as a door that wasn’t shut, causing the dome light to stay on. Here are some helpful tips I have found.

Parasitic Drain

A car’s battery has only one purpose: to start the car. It is not designed to run the accessories, such as the stereo, dome light, or other electrical features of our car.

Parasitic drain is caused by components in your vehicle continuing to run after the key is turned off. If you are planning on sitting in the car for an extended period it is always a good idea to start the vehicle when accessories are in use to prevent a no start situation.

Some parasitic drain from items such as the clock and security system are normal. However, in the event there are electrical problems the drain from even these can increase and draw the battery down.

Bad Charging system

If your vehicles charging system is not functioning properly, your vehicles battery can drain even while you are driving.

Many newer vehicles power up the lights, radio and other systems from the alternator, which can make the battery drain worse than normal when there is a charging problem. If this is the case, a charging system diagnosis will need to be performed.

The alternator recharges the battery and powers all of the electronics for the vehicle while driving.

Old Battery

If your battery is old, it might not hold a full charge. If your vehicle cranks over slowly or sometimes will not start, it is very possible the battery needs replacement. Vehicle batteries should be replaced every 4-5 years.

Having a battery that will not start your car or hold a charge is very frustrating, I am sure we have all been there!

I hope this information was helpful to all of our loyal reader here in Beaverton we do truly appreciate all of you. I can be reached at or on my cell phone (503) 930-1493

Larry’s specialty is locating cars, even hard to find cars, for everyday folk. He has been in the automotive industry for over 35 years and has several degrees in automotive technology.