I have a 1985 with 75K miles on it. When I turn the ignition switch to start, I hear one semi-click, all the lights go out, and the battery voltage drops to 1.8 Volts and remains there. So I figure I have a short, but here is the weird part. After I disconnect the battery and reconnect it, the battery voltage jumps back up to 12.3 until I try to start it again. So somehow I am clearing up the short by discnnecting and reconnecting the battery. Does anybody has any ideas what this could be?

Thanks

 

have you tryed to jump the batt. or put a charger on it

 

Gotta be the Battery.
Have you checked?
tony

 

Check the cables at the battery and at the negative cable connection at the engine block. Sounds like connection or a bad battery. If your car is using the side mount terminals take them off the battery and inspect, even though they may look good when connected it may look real bad underneath the terminal where the connection point is that is most critical.

 

You don't have a short circuit, you have a battery with high internal resistance that cannot deliver much current. Probably one or more cells have little amp hour capacity. A discharged battery will recover if disconnected for 10 minutes or so, but if you put a load on it, it quickly goes into total discharge. You might try to charge it up with a battery charger, but if the battery is near its guarantee limit, it is at the end of its life and I would install a new battery.

 

I don't think its the battery, but it is only 8 months old. The first day it happened I tried to jump it and that didn't help at all. . I did charge the battery overnight last night. Still no change. Maybe I'm wrong, but if it was the battery, I should get it roll over or click when jumping.

Also when I tried to jump, I still had to disconnect the battery and reconnect before the interior and dash lights would come back on.

 

^no, not always
if you have a dead cell and you try and boost the car with the battery hooked up, it won't always work!
the only way to know for sure is to disconnect your battery and try to boost the car

 

One or more cells that no longer have any appreciable amp hour capacity care not what age the battery is. Further proof that you have a defective battery is that you charged it overnight and it still has no capacity. Jumper cables cannot supply the 100+ amps a starter motor requires because the wire and the connection resistance is too large. Jumps are only to aid the battery in supplying starter current, not supply ALL of it. If you have another car, remove its battery and place it in your vette and see if it cranks the engine. If not, then you have bad battery cables or bad connections to ground and/or to the starter motor. Give a different battery known to be good a try.

 

You definately sound like you have a bad battery or at the least bad connections. If your skeptical, take the batter out and take it down to a battery shop or autozone and have them do a load test. I bet their machine will call it bad too. It is common for a bad battery to show 12 plus volts and not be able to put out much current.

 

I agree with JFB about the dead cell(s). If not a very remote chance is I had a short that was from the battery to the starter. I believe there is an inline fuse at this location also. Cost me $300 for the dealer to find the short and rewire but worth it because it drove me nuts. It an easy fix to do it yourself or check it out. :seeya

 

Check the Free stuff first. Have the battery tested Make sure the rods are not hanging out of the block.. :) Happen to my brothers car a few weeks ago. Cables, Starter..

 

I agree. (1). Don't jump the battery, install a good one. (2). The battery cable is the last thing checked and the cheapest to fix. (3). If your engine is locked-up, it's going to be expensive.
I'm betting a new battery will solve this mystery.
Mark

 

I concur with JFB. I once had a car that would not start, turned out to be a faulty ground. I would check the negative cable and confirm solid chassis ground. :iagree:

 

I must agree with the battery or cable people.If it was a short and your battery was pushing 700amps, it wouldn't take to long to find it.Something would burst into flames.Does the starter turn red hot?If it's a manual can you push the car and turn over the motor? :chevy

 

:iagree: BATTERY is cactus! (Or terminals are really crappy)

Similar thing happened to my Harley Fatboy the other week; only 30k on it and I got real depressed and started to think "what the?" Starter...solenoid...charged the battery and off she went; sometimes when looking for a solution we bypass THE most simple things that once we would have thought of FIRST!

Same scenario with a mates C4 recently; I was convinced it was battery - and it was. They don't make em like they used to!! :yesnod:

 

JFB,

I agree with everything but this.

A GOOD set of jumper cables will start a car with no battery. The problem is that most of the cheap butt cables that come with these so called emergency kits are garbage. They're more of a hazzard than a help. The wires are so small that they introduce so much resistance that they can actually burn up! Feel how hot they get sometime, it's scary.

A really good quality set of jumper cables will do a lot more than you think they will. I've jumped my car off of a lawnmower with my jumper cables.

 

...Your lawnmower is 12volts??

And wouldn't you need a battery at the other end of the jumper leads to start the car? hehee Sorry; couldn't resist THAT one! :crazy:

 

Yes my riding lawnmower has a 12 volt system. Although in theory you could clamp the jumper cables directly to the battery cables if you wanted.

I had a Die Hard battery that went south on me one day, it wasn't even putting out enough juice to keep the car running with all my electric accessories. I had to jump the car and it was running alright. I was driving in traffic and it just died. It was so dead that I couldn't even pop the clutch and get it going. With a hot battery I can start my car in less than it's own length with the clutch. With this battery I couldn't do it from 30 MPH!!!

The interesting thing about alternators is that they won't put out any voltage unless there is some voltage being supplied. In my case I must have dropped below that supply voltage and so without a battery, and without alternator output the car just died. My dad came to my rescue in his Ford :smash: :smash:

We connected the jumper cables (good ones) and it started right up. I let it run in the parking lot for several minutes. Since his battery was there supplying voltage that allowed my alternator to have an output. Now my output served to charge his battery, and mine too. It charged mine enough to keep it running. After several minutes I was able to limp home. My battery didn't really need to put out any current, it just had to supply a voltage large enough for the alternator to see it and charge. That's exactly what we did. I drove the car home, appox 6 miles. When I got home I shut it off and immediately tried to start it back again. Nothing, nada, dead.

I put a charger on it and let it go for a few hours. After I had dinner I came back out and tried the car. I took the charger off, the battery showed 12.5 volts. I tried to crank it and it went to something like 3 volts. I replaced the battery and all has been fine since. :cheers:

 

Sounds like battery... check cables, ground and in-line fuze...

 

Yes, I FIGURED you were talking about a ride-on mower; I just had visions of you frantically zipping away on a normal push mower!! :lol:

Yes, Fords are good for jump starts :)

Yes; batteries are like that, thats why auto electricians use load testers

You've reminded me (thanks a LOT!!) of my first car; a crappy little thing fom the UK called a Hillman 'IMP' (Sounds like? Rhymes with?) - very true...
I once started it, then out of curiousity, pulled off the battery lead - IT KEPT GOING!! ...For a 17 year old; I came close to believing it was possessed by the devil! :reddevil hehehe