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Discussion Starter #1
Just recently I have discovered a draw somewhere on my 69 nova. I tested my alt, and found out that it wasn't charging so I replaced it. I charged the battery and it was stone dead yesterday. The weird thing is when I turn my on/off switch to ON the volt meter shows the draw, when the switch is off, the draw doesn't show on the meter. BUT it still must be drawing somewhere b/c the battery is going dead. One thing I noticed is my indicator light for the line lock was disconnected (1 side of the light), could this be considered a draw? This problem did not occur last year, and the only thing I added over the winter was a new fuel system, and two gauges with loights on the hood. Can anyone suggest a certain area to start with?
Any feedback would be great!

thanx Mike
 

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Do I understand this correctly?

1. With your ignition switch off, your voltmeter reads about 12v.

2. When you turn the ignition switch on, the meter reads about 8.5v.

There isn't much on your car that can create that large a drop across the battery except the starter motor, assuming the connections are correct.

If you disconnect the positive lead(s) of the battery and put a test light in series with the lead(s) you should be able to see it glow if you have a small current leak while the ignition is off. Start disconnecting wires until the lamp goes out. Be aware of connections that are always on, like the cigarette lighter, interior lights, glovebox lights, some radios, your voltmeter, etc.
 

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Discussion Starter #3
t

Hey Mike I have a few questions

Will a bad ground cause a draw?

What if something is not properly grounded, will that cause a draw?
 

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A bad ground won't cause current to flow, just the opposite. It will cause current not to flow where it is supposed to and possibly flow somewhere else. Current takes the path of least resistance.
 

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What may be quicker than Mike's suggestion of pulling wires is to pull all the fuses out of the panel. If there is still a draw you are down to a hot circuit. If no draw, start putting fuses back in until you find the draw, then start pulling connections.
 

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Discussion Starter #6
draw

Hey Mike I pulled the postive lead from the battery, and put the test light in series, then hooked it back up, and the test light did not light up. I tried this both times with the switch on then off. Even though the light didn't light up, is there a chance that theres still a draw?

thanx Mike
 

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If you disconnect the battery and put the test light in series it will glow if you have a current draw. If you hook the battery back up you take the test light out of the circuit.
 

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Mike Goble said:
If you disconnect the battery and put the test light in series it will glow if you have a current draw.
then just pull one fuse at a time until the test light stops glowing.....whatever circuit causes the test light to go out when you pull the fuse is the circuit that is causing the problem.....BTW dont forget the dome lights that may be on because you have the door open....just pull the bulb to the dome light while you are testing as it will cause the test light to glow too...BTW if the current draw is really low the test light will still glow but just very faintly...you will have to look really hard to see the glow...good luck;) :)
 

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Discussion Starter #9
draw

well I guess I don't have a draw then, b/c when I put the test light in series with the battery it didn't light up. Maybe I'll look a little closer tonight to see if it lights up real faint.
 

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i had a mysteryious draw on my batt before, checked every wire w a amp meter, couldnt find it anywhere, so i eventually put a one way diode in the main power wire that feeds all the acc's ....cured my draw

i guess it didnt really cure my draw just didnt let it get to the battery, battery stayed charged, didnt have any problems w it after that
 

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I've always tested for draws using the negative side of the battery.
Disconnect the negative side hook my test light up in series and if it glows, start pulling fuses to isolate circut.
 

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Rayndawg99 said:
I've always tested for draws using the negative side of the battery.
Disconnect the negative side hook my test light up in series and if it glows, start pulling fuses to isolate circut.
Thats correct. Your draw is probably the alternator. First off, when you said you wern't charging did you check your voltage regulator? (assuming you have an external regulator as per a 69) Take the neg batt cable off, Clip the test light to the batt post, and stick the probe on the cable clamp. If the lights on (bright) then unplug the regulator. If it goes out, them swap the regulator out. if you have an internal-regulator alternator (and I'm assuming you know the difference) then unplug the alternator (or with a one-wire unbolt the wire) Most heavy draws are electric motors (stater, blower motor, alternator) Newer alternators have diodes that go bad, older ones use a external mechanical regulator that can the contacts can burn closed, springs break, ect). Starters and blower motors are a rarity going bad (draw-wise) but I've seen it happen. The correct way to measure a draw is with a meter that measures milliamps, but this really only applys to newer vehicles and the test light method is fine for this.
 
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