I have a 2005 Hyundai Tuscon. If we go out of town, or any time we don’t drive the Tuscan for three days or more we always come back to a dead battery. I mean really dead. I mean, get a new battery dead. Since 2005 when we bought the vehicle new, we’ve had nine—9—new batteries put in. The last one was a heavy duty battery recommended by the dealer.
This problem started after the dealer replaced the OEM radio. We’ve had multiple checks done on the engine to find out where the (battery) draw is coming from. I researched and found a Hyundai Technical Service Bulletin saying that the problem is from a defective stereo. But my dealer says they can’t locate the problem.
We’ve also had the battery posts cleaned and other things done.
The vehicle runs fine and has had few problems except for this nagging battery problem.
Can you go to a different dealer? This really shouldn’t be that hard to figure out if an ammeter is connected to the battery.
Regardless, pull the fuse for the stereo each time you leave the car for a while. If that fixes the issue, then you know the problem is with the stereo or something else on that circuit. If it doesn’t, then start pulling other fuses to find the circuit with the problem.
Until you find the drain, you could get a battery “maintainer” or “conditioner” to keep the battery up when you know it’ll be sitting for more than a day.
We’ve pulled the fuses. That didn’t reveal anything. We’ve thought about a maintainer/conditioner, but that’s just a bandaid. It seems as though we shouldn’t have to do that on something that should be taken for granted (starting a car).
Forget the dealer…Find an independent auto-electrician and find the parasitic drain or disconnect the negative battery cable when the vehicle will not be used…
From what you say about the problem it seems this would be a pretty easy issue to solve. Perhaps there is a delay in when the problem happens after the car is parked. Even so, it seems it shouldn’t be real difficult. The CD player is a common problem for this kind of thing. Here is a link that will show you how this kind of problem is tracked down and eliminated.