help! I think I have a short
Thread Starter
Drifting
Joined: Mar 2001
Posts: 1,600
Likes: 0
From: Valencia (near LA) CA
help! I think I have a short
I noticed that the batt gauge was showing negative numbers while I was driving. If I turned off everything and rev the engine to 4000 rpms I would still be below 0. I parked the car and went on vacation and came back to find the battery completely dead :(
I assume that there is a short somewhere. How do I go about finding it?
Also, did I just ruin my new optima battery by letting it drain completely?
Thanks,
~Jay
[Modified by Jay M, 5:11 PM 2/1/2004]
I assume that there is a short somewhere. How do I go about finding it?
Also, did I just ruin my new optima battery by letting it drain completely?
Thanks,
~Jay
[Modified by Jay M, 5:11 PM 2/1/2004]
Pro
Joined: Aug 1999
Posts: 749
Likes: 0
From: Perth,Western Australia,Australia
Re: help! I think I have a short (Jay M)
Could be that your alternator is faulty,take it off & take it to an auto electric shop along with you battery to have them both checked.Also a good idea to check the main ground cable coming from the negetive side of the battery,to see if it's earthed to the chassis properly.
Neil.
Neil.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Re: help! I think I have a short (Jay M)
:iagree: Sounds like bad alt. Unless you have a massive ground and the alt can't keep up? Try testing the alt first. Next I'd look for burnt wiring. Next try pulling just one fuse at a time to isolate ground.
Happy hunting. :seeya
Happy hunting. :seeya
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Re: help! I think I have a short (cardo0)
Since you have aq 68, you might want to take a shortcut and pull the wiper fuse first and see if that stops the drain. If not you can proceed in a methodical fashion. MJ
Thread Starter
Drifting
Joined: Mar 2001
Posts: 1,600
Likes: 0
From: Valencia (near LA) CA
Re: help! I think I have a short (MNJack)
Thaks for the help,
Here's what I have done so far:
I attached an ohm meter to the battery terminals. Then I pulled the fuses, one at a time to see if any would make the resistance drop. None of them made any difference. Closing the door caused a slight drop.
One thing that made a major difference was disconnecting the blue and white wires from the alternator. ( I think that's what color they are) I left the red and black ones attached.
The wiring harness is all new.
I have the type of alt with an external regulator.
The regulator was repalced and the Alt rebuilt about 6 months ago. Everything was fine until a few weeks ago.
The alt is a 93 amp, and I have a 500watt stereo and dual spal fans. I added the stereo about a month ago.
I also had Lojack installed about 6 weeks ago. They hid it in the car so I have no idea if it could be the problem.
Any thoughts? The place that rebuilt the alternator is a quality shop if it is defective they will take care of it. But if it isn't I don't want to pay them to search for an electrical problem$$$$
Thanks,
~Jay
Here's what I have done so far:
I attached an ohm meter to the battery terminals. Then I pulled the fuses, one at a time to see if any would make the resistance drop. None of them made any difference. Closing the door caused a slight drop.
One thing that made a major difference was disconnecting the blue and white wires from the alternator. ( I think that's what color they are) I left the red and black ones attached.
The wiring harness is all new.
I have the type of alt with an external regulator.
The regulator was repalced and the Alt rebuilt about 6 months ago. Everything was fine until a few weeks ago.
The alt is a 93 amp, and I have a 500watt stereo and dual spal fans. I added the stereo about a month ago.
I also had Lojack installed about 6 weeks ago. They hid it in the car so I have no idea if it could be the problem.
Any thoughts? The place that rebuilt the alternator is a quality shop if it is defective they will take care of it. But if it isn't I don't want to pay them to search for an electrical problem$$$$
Thanks,
~Jay
Pro
Joined: Aug 1999
Posts: 749
Likes: 0
From: Perth,Western Australia,Australia
Re: help! I think I have a short (Jay M)
Not a big job to remove the alternator,regulator & battery.Then take them in to get checked.It will make your job of finding the fault a lot easier if you can eliminate those components as the problem.
Neil.
Neil.
Heel & Toe
Joined: Dec 2003
Posts: 17
Likes: 0
From: Boyertown Pa
Re: help! I think I have a short (Jay M)
Based on your first post, the condition you describe indicates a no charge condition. That would indicate either the alt or reg is not functioning. There is a way to bypass the reg and find out if the alt is charging.I know that with Mopars you have to remove the field wire at the alt and run a ground wire to the field terminal. I'm not sure with the bowtie although I believe it's the same. But before you do check with someone who is familar with the Delco system. Also when you do this there is NO regular control so don't stay overly long here as the alt will put out all she can at that RPM. If you still have no output the alt is at fault.If you have amperage output the reg is bad.
Your battery should recharge if you didn't cook a cell. Make sure the plates are covered with solution, if their not add distilled water untill they are. SLOW charge the battery until your gravity is in the 1250/1300 range, or if your using a float type hydrometer all the ***** float in each cell. If one cell checks bad the battery is shot. It will not hold a charge.
Your battery should recharge if you didn't cook a cell. Make sure the plates are covered with solution, if their not add distilled water untill they are. SLOW charge the battery until your gravity is in the 1250/1300 range, or if your using a float type hydrometer all the ***** float in each cell. If one cell checks bad the battery is shot. It will not hold a charge.
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Thread Starter
Drifting
Joined: Mar 2001
Posts: 1,600
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From: Valencia (near LA) CA
Re: help! I think I have a short (DennyM)
ok, i took the battery out of the car and took it to the shop.
Their little machine said it had a bad cell.
I took the battery back to costco and got a new one.
I put the new battery in the car, and started it up.... at 1800rpms the voltage meter was pegged!! and the lights were so bright they looked like halogen...and that was just the interior;)
at 900 rpms the meter was at about 14V but as soon as I reved the engine the meter was pegged.
So I turned of the car and the battery was making a gurgling sound.
My guess is that I have a bad regulator and that fried the old battery.
What do you think?
thanks,
~Jay
Their little machine said it had a bad cell.
I took the battery back to costco and got a new one.
I put the new battery in the car, and started it up.... at 1800rpms the voltage meter was pegged!! and the lights were so bright they looked like halogen...and that was just the interior;)
at 900 rpms the meter was at about 14V but as soon as I reved the engine the meter was pegged.
So I turned of the car and the battery was making a gurgling sound.
My guess is that I have a bad regulator and that fried the old battery.
What do you think?
thanks,
~Jay
Pro
Joined: Aug 1999
Posts: 749
Likes: 0
From: Perth,Western Australia,Australia
Re: help! I think I have a short (Jay M)
Definately sounds like the regulator is faulty,even at high revs the regulator should hold the voltage at 14,5v max.Take it out & have it checked.
Neil.
Neil.
Heel & Toe
Joined: Dec 2003
Posts: 17
Likes: 0
From: Boyertown Pa
Re: help! I think I have a short (Jay M)
Jay
I hope you solved the problem. It sounds like the reg is bad, in that it won't control the voltage put out by the alt. The gurgling sound you heard was the battery cooking. 13.8 to 14.5 volts is normal charging rate depending on the charge requirements of the battery.
Denny
I hope you solved the problem. It sounds like the reg is bad, in that it won't control the voltage put out by the alt. The gurgling sound you heard was the battery cooking. 13.8 to 14.5 volts is normal charging rate depending on the charge requirements of the battery.
Denny
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Re: help! I think I have a short (Jay M)
So I turned of the car and the battery was making a gurgling sound
This is a bad regulator. I had the same thing happen on my 79. Boiled the battery really good. If I were you I would probably spend a little time with some baking soda and water in the battery box to nuetralize the battery acid that has boiled out. Don't let any baking soda in the battery. Baking soda will neutralize the acid. I was lucky I caught mine before the battery was ruined. My radio kept turning off every time the voltage got too high. Then when the car would come to idle, stop sign, the radio would come back on. I finally caught a glimpse of the voltmeter pegging. :crazy: