I got this '65 Chevy truck together... I put a stereo in it, amp... the whole bit... and it kills the battery over night. I took the battery back to where I got it... it's an Optima, so they gave me a new one... but, I'm still wondering, what is an acceptable amount of amperage draw on a system? I put my volt/ohm meter between the negative lead and the negative post...and it registers 1. and change... So... if it is too much... what kinds of things can cause a draw... besides the stereo? I pulled fuses, one by one... and it seemed to stay the same... Thanks guys, Sam.
if its drawing a little over one amp all the time, i'd say its not your stereo system. i'd be looking for a dead short someplace in the harness. start wher you made any connections for your new stereo, never know you might have abraided the insulation on a wire and its grounding out T
Did you tricklecharge the Bat before installing it? Lots of the ones we get in at the shop are close to dead out of the box.
The battery may be dead out of the box but you should not have any current draw (except for the clock) with the key off, I'd suspect a short as well.
Sam were you measuring DC current or volts? On most meters you have to change the leads where they plug into the VOM from voltage to amperage. Small draw could be seen from the power to the stereo clock when the ignition is turned off.
I would be looking for a bad diode in the alternator. Check to see if the battery lead is drawing Amperage with the motor off. i.e. place ampmeter betweem batt. lead & batt. post on alt.
May or may not be helpful info -But I went thru that with my sons first car/& HUGE stereo....... It had an amp that was about 20" long and a speaker box as big as the trunk was and yet another that replaced the back seat....... we finally put in two full size 950 CCA batterys and a 100 amp custom alternator with dual belts/2 groove pulleys..... worked perfect till one weekend at Tech school -it was all stolen.....that fixed it .
Bingo...that's the first place I go to when I encounter this problem on most GM products. If the alternator checks out okay (assuming you have an internally regulated unit...if not, check your voltage regulator), then you have to find the draw elsewhere. If unplugging the stereo equipment (or any other accessories) produces no change in the draw you're reading, you can safely assume that they are not the issue. Check the wiring to circuits that are 'hot' all the time...headlights, cigarette lighter, horn, hazard flashers, brake lights, etc. Items that are hot only under 'keyed power' will normally not be the culprits in a case like this. It's a process of elimination thing. (And, personally...the first thing I would eliminate is the Optima battery...over-rated garbage from what I've seen, a good 'old school' battery will take you WAY farther!)
Ooops! In regards to your original question:Amperage draw... how much is too much? You should be able to read almost NO discernable amperage draw with everything off. You may notice a trickle of voltage if you have a stereo system with memory functions or a processor for EFI or something...but on older vehicles, you should show no readable draw on a dial gauge, and only a miniscule amount, if that, on a digital meter. Hope it helps.
amen to that. ive had two and both lost their base charges, something optima says should never happen.
I just went through something like this with my GTO. One amp makes me think there is a short. On my car is it was only drawing .23 amps, I was told it could be the regulator sticking, replaced the regulator, battery still went dead. Next I was told that the battery was no good. so I replaced the battery. Then was told could be diode in alternator. We replaced the alternator with one that has the regulator built in. Have not had any problems since.
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