Battery drain ... getting worse ... help!
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OK, I'm getting annoyed... it used to be that I could let my car sit for five days or a week and she would still start... not any more! I drove her on Friday and she wouldn't start today without a jump from a jump box.
It wasn't so dead that I needed a jump from another car, but it wouldn't have started otherwise.
I've got her set up to plug into a battery tender and that works fine, but I'd rather have her start if I forget to plug her in.
I can hear a very low whining noise when I sit in the car... could that have anything to do with it?
Any ideas on where to look for an answer would be appreciated.
Many thanks!
Denise
It wasn't so dead that I needed a jump from another car, but it wouldn't have started otherwise.
I've got her set up to plug into a battery tender and that works fine, but I'd rather have her start if I forget to plug her in.
I can hear a very low whining noise when I sit in the car... could that have anything to do with it?
Any ideas on where to look for an answer would be appreciated.
Many thanks!
Denise
#2
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"whinig" could be climate control fan mounted on the back of the dash unit (this is normal). How old is the battery? Check to make sure the front & rear lid lights go out when they are closed. Dome light goes out when doors are closed? Those are most of the easy ones. If you have a short in the wiring somewhere it takes a test meter and alot of patience (and alot of bourbon, ask me how I know)
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The best way to start to trouble shoot this is when you park the car and hear the noise, start to pull a single fuse at a time out of the fuse box. When the noise goes away look at the label on the fuse box cover as per that fuse and see what it says. Like Dead Eye says that fan on the back of the CC unit can kill the battery.. Good luck .Mike
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I got a new battery and alternator less than a year ago. Dome light is out. Rear deck lid light is out... didn't even know I had one in the front... apparently it's been burnt out since I got the car.
I do keep the front open a lot... I keep the battery tender plugged in and I'm afraid I'll drive off with it plugged in if I don't keep the front open. With the light burnt out, it shouldn't pull any power should it?
I do keep the front open a lot... I keep the battery tender plugged in and I'm afraid I'll drive off with it plugged in if I don't keep the front open. With the light burnt out, it shouldn't pull any power should it?
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I think if the front boot is open there is a light module in the car that might stay on....I think. Try to close the latch on the hood, but DO NOT forget to pull the hood release cable before you close the hood.
Oh And I have driven off with the charger plugged in, closed the garage door, and then saw the wire pulling from the ground.
Oh And I have driven off with the charger plugged in, closed the garage door, and then saw the wire pulling from the ground.
#6
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Denise,
Since buying my 993, I've been worried about battery drain, so I've always kept the interior lights in the Off position. When I open the truck or deck lids, I always depress the latch mechanism to turn the circuit off. But these lights will come on again if one of the doors are opened....
If you are worried about driving off while the battery is connected, consider one of the Porsche charger/maintainers that function through the cig lighter. I use the silver version and have been very pleased - always a strong start and there really is no way I can drive off while the car is plugged in.
The you hear a whirring noise even days after the car was last driven, then yes, there probably is an issue with the CCU or possible one of the fan resistors in the engine compartment blower ducting.
Andreas
Since buying my 993, I've been worried about battery drain, so I've always kept the interior lights in the Off position. When I open the truck or deck lids, I always depress the latch mechanism to turn the circuit off. But these lights will come on again if one of the doors are opened....
If you are worried about driving off while the battery is connected, consider one of the Porsche charger/maintainers that function through the cig lighter. I use the silver version and have been very pleased - always a strong start and there really is no way I can drive off while the car is plugged in.
The you hear a whirring noise even days after the car was last driven, then yes, there probably is an issue with the CCU or possible one of the fan resistors in the engine compartment blower ducting.
Andreas
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I had a similar problem with my battery draining about 1 to 2 days. After a great deal of troubleshooting and replacing relays and batteries I finally took the car to my mechanic. He found that the ignition switch was bad and replaced it. For whatever reason the ignition wasn't shutting power off to the accessories when the key was in the off position.
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Try the battery ground strap. Had the same symptoms and the strap ended up being the problem. Several other RL's have also experienced the same. It's cheap from Pelican Parts about $14.00 and shipping. Cheers!
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Leaving the key in the ignition will drain the battery in a week or so. As already pointed out, opening a door, the trunk or the engine lid will turn on all three sets of lights.
Measure battery drain by pulling fuses one at a time until you locate the source of the drain.
Measure battery drain by pulling fuses one at a time until you locate the source of the drain.
#10
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Leaving the key in the ignition will drain the battery in a week or so. As already pointed out, opening a door, the trunk or the engine lid will turn on all three sets of lights.
Measure battery drain by pulling fuses one at a time until you locate the source of the drain.
Measure battery drain by pulling fuses one at a time until you locate the source of the drain.
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I'm sure that this is not the case with your car, but I'll mention it all the same. My 993 would drain its battery if I failed to drive it for more than three days. It turned out that the previous owner had installed some LoJack-like device that I didn't know about. The device had its own battery, but that was long since dead, so it was pulling down my standard battery very quickly. Removing it fixed the problem.
-John
-John
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FWIW, I've been dealing with a similar issue for the past 6 months or so... tends to be very intermittent and I've replaced my battery as well.
As a data point, an indie mechanic I spoke with said that locking the car with the fob will shut down all systems (aside from "Block") and maintain battery life a lot better. Since beginning to do this, I haven't come back from a day or two away to a dead battery.
As a data point, an indie mechanic I spoke with said that locking the car with the fob will shut down all systems (aside from "Block") and maintain battery life a lot better. Since beginning to do this, I haven't come back from a day or two away to a dead battery.
#13
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If the whirring noise you heard is related to the fan in the back of the CCU running constantly that will drain the battery enough in 2-3 days that will cause a no start.
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Do a current draw test, get a ammeter & put in between the battery & + cable. See what the current draw is with the car off. That is about the only way to tell if you just have a bum battery or you are drawing to much current with the car off.