Can my car kill a battery in 2 weeks?

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The easiest and cheapest way to find a draw on a battery is, Take the positive battery terminal off.. Get a cheap test light and attach it between the battery post and the cable. If there is a draw it will light up. Leave it lit and start unplugging things until the light goes out and follow the draw until you find the part that is shorted or turned on.
 
Ideally just use your multimeter to see what the amp draw is. Should be zero in these old cars unless you have a clock.
 
Demonx2 said:
Ideally just use your multimeter to see what the amp draw is. Should be zero in these old cars unless you have a clock.
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I've posted this before. ALWAYS start with a test lamp FIRST. The light brightness will allow you to judge how heavy a draw you have. On one large draw, I even used a tail lamp to "judge" current first

If you have a large enough draw, it can damage some meters. Not all meters are well protected like Fluke, but even so, the special fuses are expensive.
 
I found part of the problem. AJ/FormS and others said that a Battery Tender would not charge the battery if the voltage was too low. And you were exactly right. At one time I knew that, but I guess I went brain dead. I took it back to the store, the battery voltage was about 0.1. They were able to charge it up so now I need to find the drain. The reason I said that it should not drain down to zero in 2 weeks, is because I had never had that problem in the last 2 years. I hate it when problems occur for no apparent reason, but that happens to everyone.

I plan to run a wire through my multimeter to see how many amps are draining - like one of you suggested. The MM goes up to 10 amps, so I should be good. Then I will go through your other suggestions in finding the leak. I've seen those threads before, but hoped it would never happen to me. HA.

Thank you all so much!
 
The last parasitic draw I had was caused by a tiny nick in the jacket of my reverse light wires next to the transmission, just enough to expose the wire and it would rub against my transmission cooler line causing a short. Just came out of nowhere.
 
g413 said:
I found part of the problem. AJ/FormS and others said that a Battery Tender would not charge the battery if the voltage was too low. And you were exactly right. At one time I knew that, but I guess I went brain dead. I took it back to the store, the battery voltage was about 0.1. They were able to charge it up so now I need to find the drain. The reason I said that it should not drain down to zero in 2 weeks, is because I had never had that problem in the last 2 years. I hate it when problems occur for no apparent reason, but that happens to everyone.

I plan to run a wire through my multimeter to see how many amps are draining - like one of you suggested. The MM goes up to 10 amps, so I should be good. Then I will go through your other suggestions in finding the leak. I've seen those threads before, but hoped it would never happen to me. HA.

Thank you all so much!
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If you have another vehicle and booster cables you can "activate" the battery that way as well. Just don't try it on a frozen battery. I would hook up the jumpers with the source NOT RUNNING and let it set for "whatever you have time for" as long as 5 minutes. This will give it a chance to build a little bit without trashing the alternator. Then start the source vehicle and let it run for maybe 5 more. DO NOT try and charge an absolutely dead battery with an alternator. Some will fail.

Then put it back on the charger and see if it "picks up"
 
Actually jumping a battery that dead with another car isn't a good idea. Save that for a last option, no other choice.
A low battery will draw current in proportion to its needs and the voltage being supplied.
Using a running car or truck the voltage will be around 14 Volts if the alternator can meet the needs.
In both vehicles watch the ammeters if so equiped.
Do not continue to send 35 or more amps through a car's charging system. That can cause damage over time.
As shown here, even a moderately discharged battery will suck 35 amps or more when supplied at 14 volts.

hotrod swinger said:
The last parasitic draw I had was caused by a tiny nick in the jacket of my reverse light wires next to the transmission, just enough to expose the wire and it would rub against my transmission cooler line causing a short. Just came out of nowhere.
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This was not the same type of situation. The NSS and reverse switch feeds are dead when the key is off.
 
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Mattax said:
This was not the same type of situation. The NSS and reverse switch feeds are dead when the key is off.
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Easy, I’m just giving him an example that these problems can sometimes happen out of this air.
 
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