Q: A previous owner installed a radio and misplaced a lead, when the heat, radio or ac is ran the battery drains what does this mean?

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I'm trying to price it out to see how much money I need to get everything fixed, the car is not mine yet, the owner as of now has had it for 3 months, everything else in the car runs perfect, she just spent $2000 replacing the battery and alternator.

My car has 172880 miles.
My car has an automatic transmission.

If the battery is new and charging system output has been measured 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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