components like the radio and clock that keep a small current to them to retain a KAM memory. So you will need to disconnect these components, usually anything with a clock on it, or a clock itself. Once you have these disconnected, with all the doors closed, you should be getting 25 to 50 milliamps between the negative cable and negative terminal. If you have a higher amperage then wait an hour for computers to shut down, then try again. If you still have higher than normal amperage then you have found a problem.

To find the culprit, remove one fuse at a time until the extra amperage disappears. Once the amperage is gone, check the service manual to find all the components connected to this fuse. Now re-install the fuse and try disconnecting each of the components connected to that fuse one at a time until the problem goes away, when it does, you have found the problem.

If you have removed all the fuses and the amperage is still there, then you may have a shorted wire somewhere, or a loose ground. You could also have a high resistance on a wire that is holding on by a strand. The low strand amount of wire with the high current creates a high resistance which acts like a load, and will eventually drain your battery. You will need to painstakingly check all the wires and connectors for insulation damage, excessive kinking, or extreme corrosion. If all looks good to you, then it's time to check the battery itself.

To check the battery, disconnect the positive terminal and negative terminal from the battery. Now hook your red lead to the positive and the black lead to the negative  (black) terminal. You should read around 12.6 to 12.9 volts DC on a charged battery (75% or greater), with a specific gravity weight of 1.265 with a hydrometer. Now leave the battery sit overnight, and check it again after 12 hours or so. You should have the same amount of voltage, if you do not, then your battery is most likely on it's way out. Also, batteries can show full voltage and have no CCA (cold crank amps) left in them, in that case, the battery is worn out and will need replaced. The best way to check for this is to take your battery to your local auto parts store, most will check them on a load for free.

Checking for a drain can be time consuming and frustrating, but taking the time to find it will save time and money in the long run. Have fun and be safe as always.

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