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Q: Parasitic drain on battery.

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I have a parasitic battery drain. The battery still shows a current of 1.3 amps with key out of the ignition after 15 to 20 minutes. I have to cycle power on the PCM in order to clear the circuit and stop the current drain.

Hello, it sounds like you are really close to a solution since you know what is causing the draw. I would check with the relay that powers up the PCM. Locate the PCM relay in your owner’s manual or fuse box lid and pull the relay. If the relay is removed and the draw goes away, re-install that relay and see if it returns. If the draw does not return then I would suspect the relay of sticking and replace the relay. If the draw returns with the relay installed, then swap it with a like relay and see if the draw goes away. If the draw goes away, it is a stuck relay. If the draw returns, you will have to see what is commanding that relay to be energized. If you are unable to find the cause you might need the aid of a mechanic to find the source of the draw.

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