2014 Ford Fusion intermittently goes dead after sitting for a day or more. The fist dealership found nothing wrong and it didn't happen again for several months. A different dealership replaced the battery and it worked fine for awhile. Same dealership then replaced the audio control module claiming it had a draw. Two weeks later, same problem! It belongs to my daughter who is away at college and it's very dangerous for her to never know if her car is going to be dead when she gets out to the parking lot! Sometimes it's a week, sometimes months before it occurs again. Sometimes it's been sitting for 1 day, sometimes 3. It has happened in cold weather and in warm weather. And no one seems to be able to figure out what is causing it! Any help or ideas to consider will be greatly appreciated! Thank you!
My car has 30000 miles.
My car has an automatic transmission.
You could have an intermittent ground connection, or other poor connection in the starting circuit or other main circuit. Such a problem would have nothing to do with the charging circuit or the battery. If the problem is not in the wiring, the charging system could be working intermittently and consequently, unbeknownst to the operator, occasionally leaving one with a dead battery at the conclusion of a trip. Or, there could be a parasitic power draw. Ruling the charging system in or out is easy as all you have to do is temporarily wire in an ammeter (or voltmeter) to keep an eye on alternator output as you drive the car. If the gauge(s) show normal output, then there is likely a phantom load that continues even when the car is off. Phantom loads can be tracked down with data loggers or if the problem is constant (not intermittent) by simply connecting an ammeter in series at the battery ahead of each major circuit. The diagnostic then travels from there (as a circuit trace) to pinpoint the fault. If you desire a resolution to this, the recommended service is an electrical circuit/component diagnostic. In the course of that, the mechanic will pinpoint the fault and get it repaired. 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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