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Undead battery

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Old 07-27-2010 | 10:56 PM
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Default Undead battery

Having battery + window problems.

My battery won't hold a charge. I went through the Clark's troubleshooting guide, and my ammeter claims 60 mA with engine off, right where it should be, when recharged.

Working on the switches for my windows. The passenger switch turns out to be a mess; needs a cleaning and reconstruction, and the window won't go down.

Here's the problem and putting it together would be great help: I moved a functional switch to the driver's side passenger's window location, and the window still won't budge. From what I've read, that means bigger problems than just the switch, since the power first comes to the driver's side, then the passenger's side, for the passenger window. Looks like it might be the motor, but I have some troubleshooting.

Meanwhile, with a dead battery (engine won't turn over, door "dings" and dash lights come on, though) and keys out of the ignition, my driver's window switch is functional. I'm assuming that even though the battery "looked" good, there's a short somewhere towards the window?

To test this, could I pull the window fuse, recharge the battery, and see if my battery holds its charge? I'm thinking this would prove the draining is coming from the driver's side window, via a short that I would then need to troubleshoot.

Thoughts? Thanks.
Old 07-28-2010 | 12:14 AM
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I don't know what in the window motor could draw just a little power? There was a thread a couple days ago to the effect that there is a connector that feeds everything in the door, down near the jamb, under the dash. Take a look at that.

You've gone to a lot of trouble for a part (battery) that has a definite lifespan, and fails suddenly without warning. How old is it? What is the voltage a day after charging and left disconnected? If it's less than 12.6, it's probably sulphated or "poisoned".
Old 07-28-2010 | 12:20 AM
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True. I'll take a look at the post. Battery is brand-new (2 months) and is 12.6 +/- 0.1 when charged, according to dash.
Old 07-28-2010 | 12:31 AM
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My dash voltmeter reads just over 12 when a digital VOM shows 13.7 at the battery; not to be trusted for diagnosis.
Old 07-28-2010 | 12:38 AM
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Do your door switches work (in other words, does the cabin light turn on/off when you open/close the doors)?

If not, that can be the source of a current drain.

After you turn the car off, power is provided to the windows until a door is opened (in order to allow you to close the window before getting out of the car.)

If the door open is never detected because of a bad door switch, the power to the windows is never shut off, and this can drain a battery over time.
Old 07-28-2010 | 12:51 AM
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Originally Posted by Mark944na86
...

If the door open is never detected because of a bad door switch, the power to the windows is never shut off, and this can drain a battery over time.
I don't see what would actually consume power if that happened; nothing is going to the motor or the window would be moving.
Old 07-28-2010 | 11:04 PM
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I've heard actually that this problem can drain power. I pulled the door switch and cleaned it; was in not great shape. Putting back and charging battery to try again.
Old 07-29-2010 | 12:08 AM
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Try disconecting the negative battery cable at the battery put a test light in between the neg cable and the battery post if the light lites up then start pulling fuses till you see which fuse it letting power through then you should know what is draining the battery.



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