how to find/isloate a constant voltage draw?

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I am having a major brain fart, so sorry.

whats the trick to finding a constant voltage draw when the car is off? I have done(and read it a 100 times) it before can't remember now.

something like, disconect the neg batt cable, hook a test light up between the cable and battery, start pulling fuses untill the light goes off and that isolates the circut? is this correct? for some reason it doesnt seem right ???

I am 99% sure i know what it is, I have the new(white/red) wire I had to add for the alt/reg swap on the 45 going to the wrong fuse on the firewall and its sucking the battery down somehow, I have a feeling it shouldnt be going to a fuse with constant power.......its killed the batt(new BTW) for the last 2 days.......about sense I swaped in the alt ::)
 
Sounds about right, but you might want a DVOM instead of the the test light. If the draw is slight, or if there is more than one, a DVOM might be a better indicator.
 
I would think you would need to set your meter to read current (not voltage). But if your leak is drawing more than about 2 Amps, you might blow the fuze in your meter (depending on it's ratings)

If you set your meter to read voltage, it will block the leak (no current will flow), and you should show the same voltage drop all the time. Actually, I liked the lightbulb idea. I guess you could use a taillight bulb and socket (to get the wires to connect to the terminals.

Good Luck -

Rocky
 
What did you install and why did it require wiring other than stock? Did you install a 1-wire alt with integral regulator?
 
no GM stuff.......

I replaced the 40 year old generator(and mount) the gen wasnt working, its being rebuilt(and put in a box). I installed a OEM 65 alt and matching regulator(new).Seeing how the generator and its reg are different wiring, I needed to run one new wire from the reg(for the alt) to the fusepanel(on an 67 cruiser this is the white/red wire) , on the reg it says IGN. I just had it with constat power, it should have been switched with the IGN.....and I thought it was..........quess not :doh:

thanks guys for comfirming what I thought I knew :)



[quote author=spotcruiser link=board=1;threadid=17076;start=msg165362#msg165362 date=1085716474]
What did you install and why did it require wiring other than stock? Did you install a 1-wire alt with integral regulator?
[/quote]
 
yeah the procedure is the correct one, but you already know the problem. Your alt actualy need a little bit of current to convert the mechanical enery from the engine to electrical energy. When the engine isnt turning you dont want the alt to use that energy, and run down your battery. Thats why the wire should go to a switched source of voltage. :)

Dave
 
[quote author=Landpimp link=board=1;threadid=17076;start=msg165367#msg165367 date=1085717187]
no GM stuff.......[/quote]

bloody purists! :o
 
thanks Dave, I was going by my other 65 fj40(with an alt) and from the OEM wiring diagrams when I hooked up the wire, didn't occure to me that the fuse block was set up different, but opon closer inspection....they were ;)

good info on how the alt works....makes sense.

[quote author=Davee link=board=1;threadid=17076;start=msg165374#msg165374 date=1085717871]
yeah the procedure is the correct one, but you already know the problem. Your alt actualy need a little bit of current to convert the mechanical enery from the engine to electrical energy. When the engine isnt turning you dont want the alt to use that energy, and run down your battery. Thats why the wire should go to a switched source of voltage. :)

Dave
[/quote]
 
I got it sorted out, the fuse panels changed for the gen vrs alt 65's, I just had it hooked up the wrong spot on the panel....it had constat power, moved it to fuse with power when key on........all fixed :)
 

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