Gremlins.....

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Yota
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Gremlins.....

Post by Yota »

so here's the situation. wednesday night, i go to work, get off thursday morning, drive home, everything's cool. didn't drive anywhere thursday, until that night when i had to go to work again. so i go out to start up my truck, and the battery's dead. won't start. so i had to borrow a car to get to work and back (man, i hate Buicks...) and then when i got home friday morning, put the battery on the charger, and as soon as it was full, put it back in the truck and she fired right up, not even any hesitation. so i figure "that's weird, wonder what happened?" and go about my business, driving over to help a buddy move some stuff. spend most of the day there, go to start my truck back up, battery's dead again. so we got it jumped and it ran fine, so i drove home, turned the engine off, and went to start it again, fired up no problem. then this morning, i go out, battery's dead again. jumped it, worked fine, happened 3 or 4 more times today. oh, and i tried it with another battery too, my optima from my Toyota, same thing.
so i finally got home and grabbed my multimeter, put it on the battery with the engine off, and it read 12.75v, but about every 5-7 seconds or so, it would drop a hundreth of a volt... so i know something's draining, all my lights, blower motor, everything's off.
finally getting to my question, any ideas what this could be? i know it might be a short somewhere, but i don't even know where to start looking. could it be the alternator? voltage regulator? 2 bad batteries? any ideas??
sorry for the long post, but i figured it would help you guys help me if you knew everything that i know. btw, i can't think of anything that might have changed between wednesday and thursday, i didn't do any work to it, or anything...

anyway, thanks for your help, i'm gonna try and make some time tomorrow to see if i can figure anything else out
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Post by fordman »

i think you remove the negative battery cable and put the tester between the battery and the cable. then making sure everything is off including the dome light. take the bulb out if you have to. once thats done pull one fuse at a time until it stops losing volts. when it stops the leak is in that circut.
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xxxtina63
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re: Gremlins.....

Post by xxxtina63 »

If it runs when you jump it and are driving, then I'd say the alternator is doing it's job. If you switch to a good battery and still no luck, I'd say it's not a battery problem. About the only thing left is cables and grounds. Also, is there something you're doing during these times? My truck always ran fine, until you turned on the lights at idle. When driving it was fine. Come to find out, a taillight was grounding so bad it would kill the engine when at idle. Took a lot of thinking and troubleshooting before I found out what the problem was.
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re: Gremlins.....

Post by jzjames »

Something moved. Off top of my head Im thinking brake light switch.
And is your radio all wired up right.
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re: Gremlins.....

Post by Leadfoot »

you are just seeing the surface charge being burnt off for any help on the subject you need to give the charging voltage with the battery connected and engine running. and a storage voltage with battery disconnected after a load has been done. before you disconnect battery turn your head lights on for 10 seconds.
WHAT ?
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Post by fordman »

one other thing don't get them wet or feed them after midnight central standard time.
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Post by rjewkes »

also check your wiring harness under the dash mine was all melted together. rewired and no problems. Good Luck.
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Yota
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re: Gremlins.....

Post by Yota »

i think fordman has the answer. i forgot about the CST stipulation and was going by PST! :lol: :hmm:

anyway, thanks for the replies... i didn't have a chance to track anything down to today, but i did have time to wire up a battery disconnect. BUT, the battery still drains when it's disconnected. nothing it still drawing power (tried the lights, ignition, etc. but nothing has juice) and i even took off the negative battery cable , and it still drains down. it's about half the speed, tho. so, i'm gonna load-check the battery tomorrow, but i don't see any way it couldn't be fried.
the fact that it discharges faster when the cables are hooked up, tho, leads me to believe that something zapped the battery. my dad seems to think the voltage regulator took a dump and is letting juice bleed back to the alternator. sound plausible?
i'm gonna be pretty busy this week doing video directing/producing for the easter production that runs all week at my church, but i'll try and find an hour here and there to try some of the things you guys suggested.... pull individual fuses, double check grounds, brake light switch, i have no radio, so i'll make sure no wires are grounding out somewhere, i'll check all the under-dash stuff, trailer brake wires... i'll get the charging and storage voltages... man, i don't know when i'm gonna do all this... i'll make time.
oh! btw, a couple weeks ago, the blinkers stopped flashing on their own, i have to manually click it. i tried a new flasher, but it didn't make any difference. (the blinkers and the hazards use the same flasher, right??)
could that have anything to do with it? i don't know, just throwing it out there...
thanks again!
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re: Gremlins.....

Post by jzjames »

Ahh. Another thought. Your flasher circuit. I may be wrong but I think that has its own blinker can...and check to see if any of those back lights are on when you turn off the key. jz
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Post by fordman »

you have two flasher units one for blinkers and one for flashers. sounds like maybe the turn signal indicator could be messed up. the short may be in the column. if the battery looses power unhooked then it could be a bad battery. and you could try changing the regulator anyway. or take and have it check at the parts store they have a way to check them out.
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re: Gremlins.....

Post by N7HO »

I had a problem with a couple of wires coming out of the fuse box in my truck. Sometimes when I'd shut the truck off, everything but the engine would stay on. Gauges, wipers, radio, turn sigs, etc. It was random, and at first I thought it was the ignition, but finally I found the wires melted together. (It was really hard to see them!) Just a thought.
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Post by 1968flareside »

You don't have a 1 wire alternator do you?
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Yota
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re: Gremlins.....

Post by Yota »

no, it's just the regular stock (type) alternator...

and just as an update, i bought a new battery and put it in, and all my problems went away. starts up just fine, and turns i think faster than when i first got the truck. so i guess it was a bad battery. i need to put a load tester on my optima, tho, and see if it's fried, or i was just not thinking straight and did something wrong, or what....
but anyway, i'm driving my truck again! now i just gotta track down why the horn doesn't work, and why the blinkers don't work. the flasher i tried swapping with a new one was a canister-type that was clipped up kinda behind the gauge panel, and i think it was the one for the hazards... i'll have to look again for another one for the blinkers...
and btw, leadfoot, it finally clicked in my head what you were saying, and i think you're exactly right. because now even when the truck sits overnight, it doesn't drain the battery. i haven't put a multi-meter on the new battery, but it makes sense that those few hundreths of a volt were just the surface charge burning off.
thanks everyone for your help!
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