STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

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Justinberni
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STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#1

Post by Justinberni » Sun Aug 30, 2015 11:54 am

Okay so about a year ago I replaced the alternator on this truck, then sold it, apparently the guy who bought it replaced it again, then I ended up getting the truck back, he also put some shitty cheap battery in it and it went as after owning it again for two months. It wouldn't hold a charge, but once I jumped it it would run just fine, so I put a known good battery in, two more months later here I am again with the same issue, my battery is dying if I let it sit for a few hours, but runs fine when jumped so I assume the alt is good.
What could cause this? No lights or anything is staying on, I do have some aftermarket electrical shit though, a stereo, amp, and electric fan, but non of it is staying on when the truck is off. I also have some LED lights I put in my bumper, they are wired to come on with the headlights, but like I said nothing is staying on, any ideas? Do you think I have some parasitic draw, or what? Help me out guys!

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#2

Post by wayno » Sun Aug 30, 2015 12:32 pm

Did you wire the LED lights to the taillights(park lights)?
Do all your headlight circuits work properly, meaning the brights work correctly, the high beam indicator light works when the brights are on, and the regular beams work correctly also.
Did you wire the stereo lights to the dash lights so they come on with the headlights?
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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#3

Post by Laecaon » Sun Aug 30, 2015 12:39 pm

Grab a multi meter, look up on youtube how to check parasitic draw, and go hunting.

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#4

Post by flatcat19 » Sun Aug 30, 2015 3:16 pm

^ That. Draw test.



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Justinberni
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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#5

Post by Justinberni » Sun Aug 30, 2015 4:31 pm

My LED lights are wired straight to just my headlights, right by the headlight plug, all my light shit works properly.
I'll do a draw test tonight when I find someone to let me barrow a voltmeter.
My stereo is wired toy fuse box, to a fuse that is hot on ignition, it's been like this for over a year so I don't think that's the issue.

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#6

Post by wayno » Sun Aug 30, 2015 4:50 pm

Justinberni » Sun Aug 30, 2015 5:31 pm wrote:My LED lights are wired straight to just my headlights, right by the headlight plug, all my light shit works properly.
I'll do a draw test tonight when I find someone to let me barrow a voltmeter.
My stereo is wired toy fuse box, to a fuse that is hot on ignition, it's been like this for over a year so I don't think that's the issue.

Are your LED lights grounded, if they are that likely could be your problem, disconnect them and see if that fixes your issue.
You see the headlight circuit in the 720 wiring harness has no ground wires after the headlight relay, if you grounded the LED lights to the body/chassis, you added a ground in a circuit that is not supposed to have a ground.
Now if you wired the LED lights using two wires in the headlight harness, possibly red/red-blue, then that should not be the issue, as the red-blue wire on the 82 seems to be the ground side of the harness, I don't know what color the wires are on your year.
You can safely wire the LED lights into the rear park/running light circuit, as they are grounded to the body/chassis.
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Justinberni
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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#7

Post by Justinberni » Sun Aug 30, 2015 5:20 pm

They are indeed grounded, never thought about that, I'll unplug them and see if my problem goes away, thanks wayne

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#8

Post by DRIVEN » Sun Aug 30, 2015 6:17 pm

If that doesn't fix it try unplugging the connector on the back of the alternator. Not the main charge wire, just the connector.
When the only tool you have is a hammer every problem starts to look like a hippy.

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#9

Post by wayno » Sun Aug 30, 2015 6:18 pm

I am not saying that is it for sure, but the headlight harness doesn't like extra grounds.
How did you wire your stereo light, to the key, or to the dash lights?
Justinberni » Sun Aug 30, 2015 6:20 pm wrote:They are indeed grounded, never thought about that, I'll unplug them and see if my problem goes away, thanks wayne
“The difference between genius and stupidly is that genius has its limits” Albert Einstein

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Justinberni
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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#10

Post by Justinberni » Sun Aug 30, 2015 6:37 pm

My stereo doesn't have its own light wire, all it has is two power wires for the whole stereo, one constant memory wire and one power wire ignition only to turn it on when I turn the ignition to on, and of course a ground and speaker wires.

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#11

Post by Justinberni » Mon Aug 31, 2015 12:21 pm

It wasn't the lights..
I got in this morning, battery gauge reads 12 volts, I try to start and as I turn key it goes down to 6, when I stop trying it goes back to close to 12, does this over and over

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#12

Post by draker » Mon Aug 31, 2015 12:26 pm

If the voltage drops below 9.6v while cranking, your battery is on its way out.

If the battery has been ran flat a few times... it's will never be the same.

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#13

Post by Laecaon » Mon Aug 31, 2015 12:36 pm

Sounds like your battery is bad. Cant handle the load.

Have you tested the voltage at the battery when running? Maybe its over charging and killing batteries. Or your Alt cant keep up with your stereo and you keep discharging/charging your battery.

What size Alternator and, what sort of stereo do you have?

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#14

Post by Justinberni » Mon Aug 31, 2015 12:44 pm

I just have some simple little pioneer deck, I do have a sub and amp hooked up to it though.
It's just a regular alt, not upgraded or anything.
My bolt gauge looks like it's around 14 when running, but I can't get an exact number off that gauge so ill go put a multimeter to it. How many volts is too much while running?
If the alt couldn't keep up then wouldn't I have problems while driving?

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#15

Post by Laecaon » Mon Aug 31, 2015 1:01 pm

If its consistently above about 14.5 Its probably too much.

You have a sub, listen to bass heavy music? Do your headlights and dash lights often dim when the bass hits? That is your alternator not keeping up. Subs and amps consume lots of power. Maybe consider a higher output alternator...

Alt not keeping up, not necessarily. I have had my alt die and driven home on just the battery. But the battery is not for running your car and all the devices inside, its for starting your car.

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#16

Post by Justinberni » Mon Aug 31, 2015 1:26 pm

My headlights don't dim when bass hits but my gauge cluster lights do.

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#17

Post by Justinberni » Mon Aug 31, 2015 1:30 pm

Could I see if my sub is the problem by doing simpler to a parasitic draw test with my engine running and sub hitting?

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#18

Post by Laecaon » Mon Aug 31, 2015 2:01 pm

Thats not a parasitic draw then...

Parasitic testing is to see if something is draining your battery over time.

Im thinking something isnt keeping the battery happy. Its more like its being used up by being discharged and charged too often.

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#19

Post by Justinberni » Mon Aug 31, 2015 2:27 pm

I meant could I test to see if it is the sub causing it by doing something similar to the parasitic draw test, how would I test it to see if the sub is the cause?

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Re: STUPID GOD DAMN BATTERY WONT HOLD CHARGE!!

#20

Post by Laecaon » Mon Aug 31, 2015 2:40 pm

Get the truck running. Turn your stereo up to normal listening levels. Volt meter across the battery. See how much the voltage drops.

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