How can I tell how much drain there is on my battery when the car is off. I find that I am often stuck with a dead battery after the car has sat for a couple days. And when it is charged, if the car doesn't fire up right away it drains quickly. THANKS!!
Try disconnecting the battery while it just sits. See if the battery still loses its charge. It just might be a battery about to go south.
Ideally you would take the negative battery cable off and connect an ammeter from the cable to the negative terminal of the battery. That would tell you how much current was being drawn from the battery but wouldn't tell you the source. You'll need to disconnect things one at a time to discover the culprit. I'd start at the fuse box.
Check your voltage regulator. I put a brand new, super whiz-bang solid state one in my 71 Mach 1, and the pig killed the battery in a day. Turns out it was putting full exciter voltage to the alternator with the key turned off. Find the post on your alt marked FLD, and check for 12V with the key off. If you have voltage you know where your drain is. If you have a one-wire alternator, then YOU have a different voltage drain, and I just typed a lot for nothing. Oh, and I look like a blowhard ***hat.
I'm guessing you disconnect the battery after you shut the car off, and it's not the battery. So to find the problem start at the battery and work your way back. It's not much fun if you end up behind your dashboard (mine was in my steering column). I'm no authority on this by a long shot, but what I did was just disconnect wires one at a time to look for a draw. I was a very happy camper once I found it. Best of luck to you!
This Is Correct, But make sure that the doors are closed and there is nothing that draws power normally while the car is not running IE: Clock, Dome Light. You can also use a test light In place of a volt meter, when you hook the test light up between the neg. battery cable and the post If there is a drain of power the test light will light up. How old is your battery? if its over 3 years old I would replace it.
Its the Chevy that is having the problem. When I park the car I have a kill switch that disconnects the battery cable right before the starter. There are only a few circuits that are not killed, radio memory, door poppers, etc... I have a feeling its the battery, but I will do a few tests first.
Most clamp-on ammeters are for AC current only. You need to make sure it's capable of reading DC current.
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