Would heavy machinery/electrical fields have an effect on my cars battery?

[gunsmith]

I finally got a new battery for my old Toyota, the old one would not work here in the middle of nowhere every once in a while.
It was 5 yrs old so I figured it was more then due for a change.
The new batt has been great BUT like my old battery every time I parked the car in the county yard ( for my part time job ) the car wouldn't start.
I assumed the batt was just weak but was a little suspicious that this location it always failed to start.
Last night the same thing with a new battery, the county yard has power poles and heavy machinery - could they be depleting my battery or affecting my charging system or something?
It doesn't seem as if I have a short if one location always produces the same result.

[never_retreat]

Odd, does it happen anywhere else?

[AJ Dual]

You'd need to take voltmeter/ammeter readings (use the 10/20A fused connctor for the Com/negative lead for this) between the negative terminal of your battery, and the disconnected negative battery lead while the car is off, both at the construction/electrical site where the drain seems to occur and elsewhere when it does not.

This would be a good start.

Generally speaking such RF or EM fields would induct currents, not drain them, although I suppose it's possible such a thing could trip a relay or some other circuit to cause a parasitic drain. However, since EM fields produced by any dipole or current loop drop off with the inverse cube law.  Which is to say very quickly. Even a few feet makes a huge difference.

Edit, came back to add: My gut feeling on this is that something about the distance of the drive to this particular location, or the nature of the drive, uphill, downhill, the time of day or temperature is probably more important, perhaps somehow affecting the alternator's ability to charge the battery while driving. And that's assuming that a string of coincident battery drains hasn't just given you the impression this location is causing it.

[gunsmith]

The county yard is in town, 20 miles away.
I've driven the car to near the yard without the batt dying, left it for the night or at least ten hours which is typical for when I drive the senior bus without needing a jump.
In the past I have needed a jump ( infrequently ) at home after a night but not since I got a new battery last week, I guess I should have it checked for a short or a drain.

[Azrael256]

No.  You'd notice a field strong enough to damage a battery.  Part of it would be the blinding flash, and part would be the loud kaboom.  Your hair would also stand up and arc between strands a la Young Einstein.

Call Car Talk before they go off the air.  They love this kind of thing.

[Tallpine]

Maybe you're parking on a hill so the electricity is running out the top of the battery ...      

Nothing logical should cause what you describe.  However, there was a place on a county road in Colorado, where everytime we drove by in a certain pickup that the engine would die.     It was downhill and you could coast a ways and then re-start it normally, but it was just like those alien things that shut off all electric power on demand.   

[230RN]

Similar thing happened in my camper.  Battery would die in the yard.  Turned out my son had put his feet up on the dash  coming back from a camping trip and happened to push in the cigarette lighter just enough that it would cycle on and off without actually popping out.  

Took a battery terminal off and stuck an ammeter in the circuit.  Watched the meter flick on and off with about a minute period.  I finally tracked it down to the lighter.  Would have happened anywhere, though, unlike your mystery.

Can't imagine what's happening in your case unless the external fields are somehow turning on circuits in the radio through the antenna or overcoming the reverse voltage on your alternator diodes by some kind of induction effect.

Is a magnetic compass affected in this area?

Terry, 230RN

[gunsmith]

I'll have have to check that out....next time I drive the bus I will park outside of the yard too

[230RN]

You might try bringing along a battery-operated AM radio as well and wander around with it, tuning it up and down the band to see if there's a strong buzzing interference in the area. The slight leakage across insulators and through the air in high voltage AC makes a lot of pretty strong harmonics.

If it is actually due to the power fields around there, you may have to enlist the help of a Ham radio operator with some additional equipment to track down why it's affecting your battery.  You may also want to check the technical service bulletins (TSBs) on your make and model to see if there's a notice on this particular problem.

Put it this way:  I would not discount the idea that the power fields could be affecting something (including the on-board computer) to drain down your battery, and nowadays, if the battery voltage falls below something like 8 or 10 volts, the onboard computer goes dead and the vehicle is unresponsive.  In the pre-computer age, you could still crank the engine and start the car with a much lower battery voltage than 10V.

I heard (but don't have actual knowledge) of a case where parking an older vehicle on an uphill incline made a mercury switch in the hood turn the under-the-hood engine compartment light on, which wasn't seen because the light was under the hood.  This drained the battery overnight.  This could also happen, I guess, with trunk lid lights, but that's not the way I heard the story.  The "fix" in this case was to reset the mercury switch in its clamp, since somehow it had got bumped out of alignment slightly.

I guess they don't use mercury switches anymore, though.  One broken mercury switch, and we're all gonna DIE!

Terry, 230RN

[gunsmith]

ah! the am radio has a ton of interference, annoying the heck outta me because usually there is something interesting on as I'm getting off work.

I'm traveling right now bblater