Georgia Fiero Club Forum

All Things Fiero => Expert Tech Advice => Topic started by: GTRS Fiero on March 07, 2018, 09:35:29 pm

Title: Battery won't stay charged
Post by: GTRS Fiero on March 07, 2018, 09:35:29 pm
Posted for oldone:
Quote from: oldone on March 07, 2018, 09:25:56 pm
all right I give up my 86 gt keeps running the battery down. nothing left on, I charge it up the next day I unplug the charger and the next day its dead?  help
Title: Re: Battery won't stay charged
Post by: GTRS Fiero on March 07, 2018, 09:37:09 pm
I would suggest that you connect your multi-meter inline between the battery and the negative terminal, set the multi-meter to AMPs, then see what the meter shows.  You can pull fuses one by one, until there is a change.  When there is a change, you've found your culprit.
Title: Re: Battery won't stay charged
Post by: Fierofool on March 07, 2018, 09:43:22 pm
When you finish charging, feel your headlight motors to see if they're hot. 
Title: Re: Battery won't stay charged
Post by: Fierofool on March 08, 2018, 01:30:44 pm
If your headlights motors aren't hot, unplug the oil pressure sending unit and let the car sit overnight.  They can short out and because they have constant 12V to them, they can drain the battery quickly.  Happened to my 86. 
Title: Re: Battery won't stay charged
Post by: Raydar on March 08, 2018, 01:40:02 pm
Quote from: Fierofool on March 08, 2018, 01:30:44 pm
...unplug the oil pressure sending unit and let the car sit overnight.  They can short out and because they have constant 12V to them, they can drain the battery quickly.  Happened to my 86.

Same thing happened to mine. And it was a brand new sending unit.
Title: Re: Battery won't stay charged
Post by: oldone on March 08, 2018, 05:06:19 pm
its to cold out right now. maybe when it gets warmer I can check it out.
Title: Re: Battery won't stay charged
Post by: Fierofool on March 17, 2018, 10:27:42 pm
Dewey, did you get a chance to check the headlight motors or unplug the oil pressure sending unit? 
Title: Re: Battery won't stay charged
Post by: oldone on March 19, 2018, 09:11:34 pm
all I`ve done is charge the battery and then let it sit a couple days and then hook up the car again and it started right up. not the battery. Charlie I don`t know where the oil sending unit is.
Title: Re: Battery won't stay charged
Post by: GTRS Fiero on March 19, 2018, 09:20:32 pm
Does this help?

Title: Re: Battery won't stay charged
Post by: oldone on March 20, 2018, 09:06:16 pm
thanks
Title: Re: Battery won't stay charged
Post by: GTRS Fiero on April 28, 2018, 10:46:04 am
Did you get this resolved?
Title: Re: Battery won't stay charged
Post by: oldone on April 29, 2018, 12:22:13 pm
no still won`t hold a charge.
Title: Re: Battery won't stay charged
Post by: GTRS Fiero on April 29, 2018, 12:52:00 pm
You could always connect an amp meter in series with the battery, check the reading for parasitic drain, then pull fuses, one at a time to check for changes.  If still no change, disconnect the oil sending unit, then the starter.
Title: Re: Battery won't stay charged
Post by: Fierofool on April 29, 2018, 01:15:58 pm
Be sure your interior lights are off.  Close the door and check.  I just helped someone else and after trying all the above suggestions, it was the dome light was on.
Title: Re: Battery won't stay charged
Post by: GTRS Fiero on April 29, 2018, 01:39:42 pm
The map lights?  Good idea.  Also, the ajar switches could be bad.
Title: Re: Battery won't stay charged
Post by: Slyp on April 29, 2018, 02:56:04 pm
Has any body tried pulling fuses, then replacing one at a time.  At least you might get a path to follow
Title: Re: Battery won't stay charged
Post by: GTRS Fiero on April 29, 2018, 03:06:41 pm
I have done it.  I just went 1 row at a time.  It helps if you have someone watching the meter.
Title: Re: Battery won't stay charged
Post by: Fierofool on April 29, 2018, 04:40:42 pm
Quote from: GTRS Fiero on April 29, 2018, 01:39:42 pm
The map lights?  Good idea.  Also, the ajar switches could be bad.

Yeah, when you're in the car with 1 foot hanging out, you don't think about the dome lights.  That individual had rolled the dimmer wheel on the light switch all the way up and locked on the center light.  He had disconnected the battery cable to keep the battery from draining.  He just happened to hook it back late in the evening and saw the dome light come on.  There was more than one light bulb that lighted at that instant. 
Title: Re: Battery won't stay charged
Post by: GTRS Fiero on April 29, 2018, 09:24:33 pm
Once I saw an engine running at night, and it was like a light show.  Lots of electrical leaks.