What Is A Battery Keeper?

Always disconnect the battery’s ground cable before performing any repair work on a vehicle. That is sound advice because it prevents accidental starts and lost fingers, or worse. It was sound advice when the engineers switched from the old DC generators to alternators because a short could destroy an alternator. It is essential with today’s cars because a short circuit could destroy highly sensitive on board computers or their sensors. It is sound advice today because of all the on board electronics but you can no longer simply disconnect the battery because of all the electronics used in today’s cars. Disconnecting the battery will cause many electronic devices to lose their programming and cause irreparable damage to other. Even a battery that appears to be totally dead has residual energy to protect the electronics. Do not disconnect a battery without plugging a "Battery Keeper" into the car’s cigarette lighter socket or power socket.

What Is A Battery Keeper?
A battery keeper is a basic device consisting of a small, 9-volt battery, the same battery used in portable radios and smoke alarms. You can make your own if you have a 12-volt power plug and a 9-volt battery snap connector lying around your shop. Just be careful to get the polarity right. Reversing the polarity of the power going to sensitive electronic can do just as much harm as removing all power from them. Buy a battery keeper. You can buy them online for less than $5.00 on Amazoncom. I keep extra ones on hand because I am always giving them to friends who like to work on their own cars.

Keep One In All Your Vehicles
It is an excellent idea to keep one in the glove compartment of your car or truck as keeping several of them in your shop. If something should happen to your battery while on the road and need to have it replaced, plug your own battery keeper in before turning your vehicle over to a strange mechanic or mechanic’s helper. Many shops allow mechanic helpers to do battery service. Mechanic’s helpers are not always well trained and may not know of the need to use a battery keeper. What is even worse the irreparable damage done to on board computers might not make itself known until days later.

There are many gadgets that the do-it-yourself mechanic needs to know about, battery keepers are just one of them. Many of them, like the battery keeper, are inexpensive, so every shade tree mechanic can afford them. Instead of listing, them all at one time, I will tell you about them, as you need them in my future articles. The best way for the new shade tree mechanic to build his or her tool kit is to build it one project at a time.