Can a cell phone charger cause parasitic draw if no cell phone is attached?

Mitlov

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My wife's ten-month-old Element is at the shop after the battery went completely dead--to the point where the power door locks wouldn't work, the sound system's memory was erased (so it needs an unlock code), and a jump-start from a Civic didn't have enough grunt to get the engine running again (a jump-start from the tow truck did, though). It had had problems consistent with a low battery for a couple weeks--dome lights only working intermittently, doors spontaneously locking for no reason (we had the auto-lock feature of the car turned off when we bought it, so it's not that).

The mechanics at the dealership insist that the battery itself is fine, it's just drained of power and needed to sit on a trickle-charger for a day. Considering my wife drives it every day and does 30-mile round trips on the highway once or twice per week, I'm skeptical.

The only thing I could think of is she has a habit of just leaving her cell phone charger plugged into the dashboard outlet all the time, and just hooks her cell phone up to it when she's in the car. Could the charger be causing parasitic draw even if there's no cell phone hooked up to it? I didn't think it could, but am I wrong here?
 

argatoga

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A poorly designed charger can.
 

Clegko

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A bad charger can, yes. But even the cheapest of the cheap shouldn't cause much parasitic power loss without showing other symptoms, like blown fuses or dead phones.
 

EyeMWing

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The mechanics at the dealership insist that the battery itself is fine, it's just drained of power and needed to sit on a trickle-charger for a day. Considering my wife drives it every day and does 30-mile round trips on the highway once or twice per week, I'm skeptical.
It can take up to 30 minutes for a lame alternator to charge back the costs of starting up the car. If it happens again, have the alternator checked.
 

prizrak

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Yeah I doubt it's the charger, they do have some draw even when phone is not plugged in but nowhere enough to cause that kind of an issue.
 

JCE

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It can take up to 30 minutes for a lame alternator to charge back the costs of starting up the car. If it happens again, have the alternator checked.
Agreed.

Get that alternator checked. Either it has lost some diodes usefulness and is dying/dead or something else is drawing your power. The alternator might be having to work too hard to charge the battery up thus causing damage to the alternator which does happen.
 

Mitlov

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Thanks everyone for the help. If the problem reoccurs, the alternator is the first thing we'll have them look at.
 

Mitlov

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It charged all day at the dealership. Drove it back to the office at 4 pm. Locked it, made sure dome lights and headlights were off. By 9 pm, when I went back out to it, dome lights were periodically fading when the engine was at idle. Drove it home. Parked it, locked it, made sure all lights were off. By 11:30 pm, when I went out to put carseats back in it, dome lights were malfunctioning again (front wouldn't turn on when set to "door," even when door was open; rear wouldn't turn on regardless of setting, but when I closed all the doors, they both came on and stayed on until I opened the door again, at which time they started functioning normally). Luckily, I got the entire thing on video. My wife will take it to the dealership to see what they say (along with a polite reminder that we know our Oregon lemon law rights and this is their second try out of three). There's no way a functioning battery and functioning alternator could go from fully charged to "low enough to cause problems" in six hours if the headlights and dome lights and everything weren't left on (which they weren't).

EDIT: The cell phone charger was not hooked up at all during this time, so we know now that's not the problem.
 
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prizrak

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It charged all day at the dealership. Drove it back to the office at 4 pm. Locked it, made sure dome lights and headlights were off. By 9 pm, when I went back out to it, dome lights were periodically fading when the engine was at idle. Drove it home. Parked it, locked it, made sure all lights were off. By 11:30 pm, when I went out to put carseats back in it, dome lights were malfunctioning again (front wouldn't turn on when set to "door," even when door was open; rear wouldn't turn on regardless of setting, but when I closed all the doors, they both came on and stayed on until I opened the door again, at which time they started functioning normally). Luckily, I got the entire thing on video. My wife will take it to the dealership to see what they say (along with a polite reminder that we know our Oregon lemon law rights and this is their second try out of three). There's no way a functioning battery and functioning alternator could go from fully charged to "low enough to cause problems" in six hours if the headlights and dome lights and everything weren't left on (which they weren't).
This sounds more like wiring gremlins than alternator/battery issue. If wiring is a problem you can have a drain somewhere that will definitely cause the battery to go flat.
 
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