Join Date: Jan 2009
Location: NE Illinois
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Measure the battery current draw when the car has been off for a while. This can be done without breaking the circuit. If you break the circuit, that will mess up the clock and radio. One more reason to maintain the voltage during the test is there may be some load that draws power for a while after it goes on, but then drops down. Keeping the current flowing will give a better indication of what the car draws overnight.
Hold one meter test lead to the chassis, and one to the negative center post of the battery. Then lift the battery connector up while maintaining contact with the center post. Note the current. Put the terminal back and tighten.
Normal draw might be 100 milliamps. If you see 500 milliamps, you will know that some accessory is drawing excessive current in the car-off state. Move that load to a switched wire.
2009 V6 4wd Base