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Lose Computer Memory?

It used to be that “in the old days” you could disconnect your battery to wire brush the posts and cables. Now I’m told that you should not disconnect the battery connections because the computers will lose their data. Is this true? If so how do you disconnect the battery to clean the posts thoroughly?

Some would say that periodically clearing the memory is a good thing. It is questionable, but there is a way to disconnect the battery without losing the memory in the ECM and radio: a battery memory setting saver. Just plug in the 9V adaptor to the cigarette lighter, and then disconnect the battery.

Alternatively, depending on the car, you can work fast and touch the cables to the post every couple of minutes to keep the capacitors charged. Just be sure all of your lights and accessories are turned off.

Disconnecting your battery will not hurt anything. You may have to reset your clock and radio presets, and the car may run a little different until the computer “relearns” the engine. It may stumble slightly on acceleration or shift at different points. After a couple of days of mixed driving, all should be normal again. I’d think the benefit of having clean battery terminals and a good connection would outweigh the minor effects of disconnecting the battery.