Ignition switch key turned to ON drains battery?

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I was doing a tire rotation this past weekend and decided to check for seized front calipers on the front of the car. While the car was in the air, I left the key in the ON position in order to switch the transmission into neutral to let the front wheels spin feely. After leaving the key in the ON position for 1 hour, a clicking noise started from under neath the hood. I than remembered that the key was left in the ON position and quickly took the key out, after which the noise went away. For the entire weekend, I did not drive or start the car after this happened as I used our other car. Yesterday, the car did not want to start in the morning. I jump started and all is fine. Did the 1 hr. in the ON position drain the entire battery and thus for the noise under the hood? Does this mean my battery is getting old if it was drained entirely in 1 hr. from just leaving the key in the ON position? What exactly is working in the vehicle when the key is in this position? I assume everything is working including the fuel pump and every where else current is flowing into?
 
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1 Hr shouldn't kill the battery, I would have your battery tested, most likely it's weak. \:\! The fuel pump will start in some vehicles and then shut-off when the system is primed. Others go based on whether or not the engine is cranking with spark. So it wouldn't be this. You are running the field in the alternator, but this is such a small draw that it shouldn't kill the battery in 1 hour. I honestly think your battery is toast.
 

Spartuss

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I'm going to check the water level again in the battery and add distilled water if needed. Would a load test at an Auto Parts store that they offer for free tell a story?
 
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It seems as though it's standing up to the load because it will start the vehicle however it doesn't stand the test of time. You could have it tested, but you might have one of those weird problems where it passes the load test but has another issue. Can you try another battery from another vehicle for the 1 hour that this battery fails? If it doesn't then you have your answer.
 

Spartuss

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Lately, I've been driving this car very little as I take the light rail into work as I work in the City. My trip is 1.5 miles each way to the light rail station and another 3 miles each way in the evening to the gym. Maybe my battery isn't getting enough charge?
 
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That's a possibility as well. On top of that, you probably have a lot of moisture and fuel in your oil, due to the engine not being at normal operating temp long enough (if at all).
 
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All the ignitions gear, in the 'ON' position, is more than likely powered up. Such as coils (coilpacks), etc. And of course, in many cars, HVAC and entertainment systems are started and running, etc. Modern car can easily have 200-300W of consumption (ie: 15-20A @ 12-14V) with just the key in "ON". That's pretty significant; car batteries are designed to give a pretty large 'kick' for startup (ie: to move a starter), but they're not really intended for long-drain applications.
 

Bill in Utah

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 Originally Posted By: Spartuss
I take highway drives on the weekend and use Pennzoil Platinum to help fight this.
Oil choice is not going to make a difference. But what info is needed is how old is the battery? And I'd bet you are NOT getting enough charge with your super short "commute". Your use of the battery is hard on it. I'd bet the battery or charging system is in need of repair. Bill
 
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 Originally Posted By: Bill in Utah
 Originally Posted By: Spartuss
I take highway drives on the weekend and use Pennzoil Platinum to help fight this.
Oil choice is not going to make a difference. But what info is needed is how old is the battery? And I'd bet you are NOT getting enough charge with your super short "commute". Your use of the battery is hard on it. I'd bet the battery or charging system is in need of repair. Bill
That's a great point... You might want to think of using a trickle charger to keep the battery topped up in between trips from home to work etc.
 
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I think you probably have a drain in the system somewhere (like an incorrectly wired amp that is always on) that isn't big enough to trip the fuse, but enough to gradually drain the battery, and you have a weak battery (1 hr shouldn't cause any issue). Also short commute reduces the amount of charge time, but still, your battery is worn out or weak, that's the main issue. Go pick up a replacement and install it, not worth investigating.
 
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 Originally Posted By: Spartuss
I take highway drives on the weekend
Well, then that should help recharge the battery. Was your cabin fan on during that 1 hour that you had the ignition on?
 

JHZR2

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+1 my wife did this the other weekend. I do notice a fair voltage drop with my key to on but the engine off, in my BMW. The car doesn't have a lot of electronics, but something draws enough to cause a voltage drop...
 
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I like pandabear's amp theory. For future reference you can turn the ignition off (or to acc) with the trans in neutral, a safety thing in case the acellerator gets jammed. Most of the time the car won't let you hold your keys unless it's in park-- but you can shut it off. I left my headlights on for two hours once and the car started right up. Those were more load than just the ignition stuff. If your battery was in good shape but moderately discharged its internal resistance would lower and it would gobble amps from the charging system. Short commutes would eventually lead to an ~85% charge (even if it started out further discharged) as compared to a 90% you'd get from long trips. This is just slightly bad for the battery, maybe you'll get 5 years instead of 6. Johnny Carson's 1982 Delorean was about the newest car that wouldn't charge the battery even if you idled and cruised around with lights, AC, and radio on all at once.
 

Spartuss

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 Originally Posted By: Quattro Pete
 Originally Posted By: Spartuss
I take highway drives on the weekend
Well, then that should help recharge the battery. Was your cabin fan on during that 1 hour that you had the ignition on?
Everything was off during this time other than the warning lights on the dash that were lit up. The battery is a Nissan OEM that's 5 years old with 71k miles on it.
 
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I have long wondered about modern ignition systems. with th eold points system, you could both drain the battery and burn up the points leaving the key on. Does it hurt anything now?
 
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 Originally Posted By: eljefino
I like pandabear's amp theory.
The quiescent power drain of car amplifiers is very small, on the order of tenths of an amp.
 
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