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CHIRPIN'INTO2nd
08-24-2004, 11:23 AM
Could one of you guys help me out?
I have an automatic '95 SC with 100k miles on it. I bought it a few months ago and It is my daily driver. I was driving home from work recently and the little red battery light on the left side of the instrument pannel went on.
I took the car in to Auto Zone and these two minions hooked up the diagnostic equipment to it and they told me my battery might be bad. I drove away and the car died at work the next day. So... I took the battery in to Auto Zone as that is where the previous owner had bought it and they charged it and told me it tested fine after that.
I popped the battery into my car and it started right up. However the
Battery light was still on.
So.... I took it to Kragen and the guy came out to my car with a little hand held device that he hooked up to my battery. He told me my charging system was not getting juice to my battery. He said it is the alternator or the voltage regulator. I bought a new alternator as the Hayes manual tells me the voltage regulator is on the alternator. I got it home and swapped it out. I did not however see the voltage regulator. I started up the car and the battery litght did not go on. Eureka! I went to sleep and started it up this morning and there it is... the freaking battery light...
Any ideas guys.
Please help.

Thanks.

Paul de Hoyos.
San Diego, California.

SuperCoupeSC91
08-24-2004, 05:21 PM
take volt meter or a Digitial multimeter and put it on volts DC and connect it to the battery when your car is running.. ur alternator could of went bad. i had a bad case once,at first i bought a ford unit paid cash went back 1 week later because they tell me it has been discontinued then i bought a power master unit from summit racing (told me it was the one for my car) (because i didnt want a cheap alternator) modified the hell out of the bracket it sits on for it to fit, get it all together and then i start it then a littloe while later on the battery light came on and i never seen it since i bought the car. so i checked with a volt meter and my volts were low and i was pissed after all this work and special ordering it threw summit racing, and then i called power master and they said they took that alternator out of there catolog and didnt know why summit racing hasnt had theres updated and now didnt recommed it. then i went to autozone and got one from them for 120 ? and dropped it in (what i didnt want to get and its been fine since now) basically if u can start your car your battery is good, if you check with a volt meter and your voltage isnt at least 13.5 or so and up your alternator is bad..check with your light on to. it should make up for the draw and not drop. and your voltage regulator is inside the alternator you wouldnt see it unless you dismantled it.. Alex L

TbirdSCFan
08-24-2004, 05:29 PM
If the alternator you bought was a rebuilt one, don't assume that its good. You need a voltmeter to check it out... and one other thing..

Buy a trickle charger and charge the battery overnight fully before you run with a new alternator. If you installed the new alt and didn't charge the battery first, it may have stressed it too much and fried it. Rebuilts don't have the best parts; the regulators are prone to failure from long duration stress. Check the charge of the battery with a "bulb" type tester which you can buy for $2-$3 at any parts store.

CHIRPIN'INTO2nd
08-31-2004, 01:44 PM
Guys, thanks for all your help...
plucked the alt... took it to kragen and had it bench tested... tested fine... poped it back in and now my battery light flashes wildly...
I am reading some old posts and some of the guys mention the pusher fan or blower fan?
What does this look like and where is it. I would like to check it as I did blow a yellow 60 amp fuse in one of the boxes in the hood right next to the battery.
I will pick up a volt meter and try to see if one of the wires has lost integrity or if I can find something else wrong.

TbirdSCFan
08-31-2004, 02:00 PM
Guys, thanks for all your help...
plucked the alt... took it to kragen and had it bench tested... tested fine...They usually do test fine when cooled down to room tempertature on the bench test; doesn't mean that its good. Reason is that it has to be load tested at higher speed than their bench tester, and the adapter harness that they use has to check the lead for the battery light. Most of the time, they are scratching their heads just to get the thing to bolt up to the test stand and make any of the needles move.. let alone check all the circuits.

Of course, you'll have he** trying to convince one of the store clowns that the alt is bad when its spinning 13.5V at 100rpm.. to them thats passing.

I will pick up a volt meter and try to see if one of the wires has lost integrity or if I can find something else wrong. Thats about all you can do.. keep a cell phone and jumper cables handy for when the alt finally goes and you get left stranded. The light will come on more and more often. When its on, check the voltage and you'll see that indeed, the alt is not doing anything.