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Q: Something draining battery maybe radio

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Bought car yesterday they jumped it to start it and they assured nothing was wrong with the car it just had been sitting for a couple days. I noticed when I turned the car off and took key out of ignition and opened and closed my doors my radio was still on.i turned the radio off by pusing the power button and no lights were on the display screen.not thinking anything about it the car was not starting the next morning.the battery is completly drained.the radio does not look like it was just put it.

My car has 170000 miles.
My car has an automatic transmission.

The diagnostic would begin with the battery. The battery should be fully charged and then load tested. If the battery passes a load test and charging system output has been measured, too, and is within specifications, the only reason a battery will discharge is if the car sits for a long period of time (batteries will self-discharge even if not used) or if there are parasitic (excess) loads on any of the car’s electrical circuits. If there is excess current flow that is slowly draining the battery, a Mechanic would use an ammeter to test all of the various circuits until the faulty circuit is found. Then that circuit is traced to find the fault and repair it. If you want these steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an electrical diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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