Battery goes dead after sitting for one day

ok. I have a 93 Chevy Astro, six cylinder. my battery started dying and I was having to keep on jumping it. well, I replaced the battery, several times, gave up for several months and decided to get her back on the road. replaced the battery “once” again and the alternator. ran for a couple of days and the next day I go to start it and nothing. no click, no nothing. had to jump it once again, drove around for about 45 minutes and then shut it off. waited and restarted again. next day, got a click and the dash lit up but no start. could it be a bad wire or the cilonoid on the starter draining the battery?..

Clean connections on both ends of both battery cables. Then the cables need to be checked to see if they are good. If that all checks out good, you need to find what is draining the battery. That is done with a parisitic draw test.

Good ideas above. Common causes are a faulty door switch, or a light that doesn’t turn off when it should, like the dome light, trunk light, glove compartment light, engine compartment light. If all that doesn’t pan out, these are the tests I’d do next

  • Before first start of the day battery should measure about 12.6 volts. Then immediately after starting the engine, 13.5-15.5 volts. What do you measure?

  • Next is measuring the battery drain current when everything is off. Should be less than 50 mA once all the computers turn off.

hum. door lock (electric, cover) broke off several months ago after I had it for a year with no problems. (bought it in 2018) after that happened it was running fine for a few months then the battery started going bad but it was beyond it’s lifetime an needed to be replaced anyway. didn’t really think anything of the passenger door lock doing this since it needs power to operate even with the engine off…

connections are clean. motor is really in good condition considering the mileage on it. couldn’t find any breaks in the wires going to the positive terminal on the battery.

when the battery is full charged, the volts on the dash show a 14.0 volts but after two days and it had started also, the volts went down from 14 to 12 to 10 to zilch… mechanic said that the drain was around 12 ( I think). I need to take it back to the mechanic and see if he can trace the drain with his voltmeter…

That is the next step

good luck, new battery in mine and it’s still happening. battery won’t hold a charge or when it is charged, dash is showiing a charge but when I shut it off and try to restart, nothing. dash lights up and no click from the starter… (puzzled)… gonna take battery back to store and try once again, if it still happens then I’m gonna head for the nearest repair shop that has a voltmeter and see if they can find the source. I’m all of options after this.

Don’t you think it is time for a shop to take over and solve this problem ?

1 Like

Is that with the engine off, before the first start of the day?

it’s been in the shop twice!.. once for the alternator (thought it had fixed the problem) and the second time it was for a bad brake line going to the rear brakes. I’m gonna take the battery back to the store and have them test it. if it’s good then I’ll take it to another shop that has a tester but even that takes money that I don’t have at the moment…

yes.
as soon as I turn the key and I watch the dash light up (electronic digital readers)…

I had also stopped in at a autoparts store to get a 8mm wrench for the side posts, the guy there also suggested that it could be a loose or bad ground wire causing it… well, we shall see come Monday.

14 volts is an unusually high battery voltage reading before the first start of the day. It should be about 12.6 volts. Something is amiss there. It could be the voltage meter reading is inaccurate. Suggest to ask your shop to figure this out.

Assuming the problem is due to a parasitic draw . . .

You could probably buy a half way decent . . . decent enough for diy use, anyways . . . and measure the draw yourself, and it’ll probably be cheaper than paying for diagnosis

If you do have excessive draw, you’re going to have to start pulling fuses until you find the culprit

There are probably lots of youtube videos showing how to do this properly

took battery back to store, turns out that it was faulty, mechanic I know said it was a complete dead cell (no cold crank amps) something about the battery being on recall from one company and about a oxide that wasn’t holding a charge. battery has a five year warranty so that is one plus on my side. they replaced it with another battery from a different company but same voltage as the previous one and so far no issues except for finding a couple of wires that was disconnected from the A.C. (under the hood)…I’m gonna have a chat with the mechanic who replaced the alternator and see why this is…

Hopefully your shop has this under control now. Glad you are back on the road w/a reliable ride.

Most cars these days have some electrical connectors that don’t connect to anything. The wiring harness is often general purpose to handle every option package available, and which connectors are actually used has to do with that car’s specific option package.

1 Like

First and foremost are those terrible electrical connections to the battery… which i am assuming is a GM style side post? Oftentimes those connections are not made correctly due to corrosion, stripped battery terminals. On just about every GM I have had to repair any electrical issues with I would cut the rubber/plastic that covers the battery terminals… The rubber goes all the way around those terminals…and I usually remove the portion between the battery and the connector on the cable as this piece of rubber usually gets in the way when connecting the battery and it also harbors corrosion that is hard to see because of the covering.

For a very quick and easy test… here is what you do… Simply remove the Hot wire that goes to the alternator and see if when you hook it back up the next day she starts… If so, you just found that your alternator is the culprit in this instance. Its a common failure that alternators exhibit. Sometimes the condition is so bad that when you come out the next day ( and have not removed any connections) you can actually notice the alternator will be warm or even hot, but for this test simply remove the hot lead from the alternator for an overnight test.

Be sure to either tape up the terminal you remove…or otherwise insulate it so that it cannot arc out on any of the surrounding metal.

If your battery was healthy the day prior and you remove the hot lead from the alternator and try it in the morning and you can get started…you need a new alternator.

A very quick and easy test… if it is not the alternator…you will then need to get more in depth with the parasitic draw. Personally I enjoy finding the culprits on these cases, but some may not share my enthusiasm in this realm. But the alternator disconnect has solved a great many of these cases for me personally, so I have no qualms about recommending you try it… It is a fairly common failure mode for alternators.

I would rather do electrical, versus a brake job

Same, I hate doing pads on my Focus…but using a meter to track down why my FR turn signal in my Odyssey wasn’t working? Much more enjoyable even if I was crawling all over the ground to check the chassis grounds (turned out to be the socket itself…which annoyingly enough is a Honda specific part that a dealership had to special order…)

1 Like