Not starting, appears to be an electrical problem

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Jeo
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Not starting, appears to be an electrical problem

Postby Jeo » Tue Aug 03, 2010 2:50 pm

Hey guys,

Little bit of back story first to set the scene. Tried to move my car for the first time in about 2 weeks, a little over a week and a half ago. Wouldn't start so I rolled it out of the garage and down the street, attempting to roll start it. Got nothing. Brought a friends car down to attempt to jump it, still nothing. You can hear the fuel pump start up, lights on dash come on, but when the key goes to start everything dies. Pushed it home, took the battery out, put it on the charger, was gone for <2 minutes and it said it was fully charged. Confused, I put the battery back in and still the same problem.

Got the multimeter out, battery shows a full 12v. Maybe the connections are dodgy? Connect the positive terminal of the battery to the positive prong of the multimeter, negative terminal of the battery to the car, negative prong of the multimeter to the chassis; get 12v. Swap everything around so we have the opposite, 12v. Connect both battery terminals to their normal connection points, 3v. Take battery out, 12v. Connect both terminals again, 3v. WTF!

Well and truly confused and annoyed at this point so I went inside and got a drink. Came out 10 minutes later to push the car in the garage and it started. Turned it off/on a couple of times, no problems. Went for a drive to my parents place about 20minutes away, left it for about an hour, started first go when I went to leave so I assumed all was well.

Car didn't move since last weekend, about a week and a half ago. Went to go to work this morning and she won't start. Get out the multimeter again and it's the same problem. Battery on it's own shows 12v, one terminal connected (doesn't matter which one) shows 12v, both connected shows 3v.

I'm going to try another battery tonight but beyond that I'm about out of ideas. Anyone seen this sort of thing happen before?
Thanks in advance :)

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sliq
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Re: Not starting, appears to be an electrical problem

Postby sliq » Tue Aug 03, 2010 3:07 pm

i had something like this happen to me.

it turned out to be the loose terminal on the battery :oops:

problem solved
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Jeo
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Re: Not starting, appears to be an electrical problem

Postby Jeo » Tue Aug 03, 2010 3:34 pm

Terminals were cleaned and tightened.

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RawSouth
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Re: Not starting, appears to be an electrical problem

Postby RawSouth » Tue Aug 03, 2010 3:43 pm

Does the battery light come on when you turn your keys?

If not it could be the EGI relay under the bonnet.
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JBT
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Re: Not starting, appears to be an electrical problem

Postby JBT » Tue Aug 03, 2010 3:44 pm

Intermittent internal short in the battery, battery terminal post (not connection) loose or short/gremlin in the car electrical system would be where I'd be looking. Can you borrow/try another battery and see if that fixes things?
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Re: Not starting, appears to be an electrical problem

Postby Jeo » Sat Aug 07, 2010 7:27 pm

JBT has it. Something is intermittently wrong with the battery.

Would hold charge for about an hour, then said only a few volts, then would go back to 12v without me touching it. Stole the battery out of my girlfriends car, worked fine. Bought a new battery. All is well.


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