Battery Light Coming On??

[00pooterSS]

I don't have the wiring diagram to your car/truck. But on a lot of vehicles the battery warning light is in series with a fuse. The small wire (exciter wire) that connects to the alternator to turn it on. So what happens is, since the bulb is connected a fuse, power runs through the bulb and out to the alternator. Then if there is an issue with the regulator the terminal that the exciter wire is connected to will become a ground and illuminate the battery warning light bulb.

Late model cars use the computer to activate the warning light but for a very long time the warning bulb was a completely isolated circuit. Meaning it was one wire from a fuse or breakout after a fuse, to the warning light, then out to the alternator. So if you had a battery warning light come on, the only thing you would look for is a ground coming out of the alternator when the bulb is illuminated.

If not you may have a short in the cluster or else where in the wiring.

$0.02

[bjtheman1]

It's too early for this shit!

Started driving to work, noticed headlights & dash lights fading in/out, then traction light started coming on/off!

Bought to hit up Vatozone for another Alternator...this will make # 3 in the past few months.

[bjtheman1]

QUESTION:

When I install this stock alternator do I need to put the stock power wire back on or can I leave my PA Performance Power Wire on???

[bjtheman1]

Alright, the fun times keep coming!

From the beginning, not too long ago replaced my battery. Shortly later started having same issues, ended up needing to replace alternator. Got a Remanufactured Alternator, then battery light would come on but go off when I hit higher rpms. Took alternator back, got a PA Performance Alternator with Power Wire. Now battery light comes on and stays on.

Well, this morning leaving for work I noticed dash lights/headlights fading and my traction dash light kept coming on. Came home, hooked up SCT/Laptop and data-logged. My Battery Voltage with car going was averaging 13.14V! I went to O'Reileys where I got my battery and they did a complete battery test, it was performing fine but he got the same low voltage readings as I did with the car running.

So, I've already contacted PA Performance about sending mine in to get it checked/replaced and I bought another Remanu. Alter. this morning in the meantime. About to install it, so frustated with all this crap

Beyond defeated! I just want to trade my car for something else right now! LOL

Installed a Remanufactured Alternator, of course the damn battery light comes on. I data-log and it's only averaging 12.20 volts with the car running. WTF????

This is just ridiculous

[LS1Goat]

Take your alt. to Autostart on Main st. in Lewisville. U can thank me later.

Sent from my SAMSUNG-SGH-I897 using Tapatalk 2

[dee]

Have you made sure all grounds are good and tight?

[bjtheman1]

Have you made sure all grounds are good and tight?

No, I don't even know where all the grounds are? There's quite a few, I'm lost here

[dee]

No, I don't even know where all the grounds are? There's quite a few, I'm lost here

Loose grounds can cause odd problems but the voltage on the new alt should be higher, your new reman could be bad.

[KBScobravert]

No, I don't even know where all the grounds are? There's quite a few, I'm lost here

Find the ground from battery to ?????. Also check to make sure the ground from chassis to block is good. Most factory will ground straight from battery to block with about a 4ga then from battery to chassis with a 8-10ga.

If you are running a typical 3g you have 2 wires to the alternator then the charge wire from alternator to battery. For a typical Ford for example: lt green/red from fuse panel hot in run to instrument cluster (which triggers the light with not enough voltage) then to the alternator to "turn it on". Next there is a white/yellow from the fuse box to the alternator that is constant 12v all times. Then you have your return which you already replaced with the PA charge wire.

If it were me:
Check continuity on lt green/red from alternator plug to cluster harness plug then from cluster harness plug to fuse box.
Check fuse (my 95 cobra it is fuse 18 and is 20amps located under the dash)
Check continuity on white/yellow from fuse box to alternator plug
Check fuse (mine is ALT fuse in the fuse box under the hood and is 20amp)
Of course you know the PA charge wire, check to make sure it ran right and tight on the fuse box lug (where mine plugs in from factory)


Last year before, during and after the Power Tour, I had a both my key on and constant wires shorting to power. Eventually it got so bad it killed my battery. Pluging the alternator in it would get warm with the key out. What was happening was the alternator was "turning on" and stayed that way till it killed the batter. I found this out when the engine was cold and the alternator was warm to the touch. Also, with the key out my battery light was "On" on the dash. Interesting it only gets voltage from the ignition swith to fuse box etc. Ooops, time to pull the harness apart. I found a small pin prick of solder (my doing) that crossed through my heat shrink and stabbed the other wire. Lesson learned. I put on a new PA 200amp anyway and replaced the charge wire to a 2ga. It was a lesson learning experience though.

[KBScobravert]

Loose grounds can cause odd problems but the voltage on the new alt should be higher, your new reman could be bad.

This. Alternator should be putting out 14.2-8 volts. If it does on the bench it will on the car unless you have a wiring issue......which I believe you do.

[01svtboy]

check the battery terminals are good and tight and free of corrosion.

[bjtheman1]

Alright, I just did voltage drop tests on the alternator output and ground circuits.
Output Circuit showed 0.15V
Ground Circuit showed 0.09V

[bjtheman1]

I took the new Remanufactured Alternator out and cleaned as well as made sure wiring was solid around there. Also, cleaned and made sure the grounds that I could find were tight. Still have no ideas where all the grounds are in this vehicle.

Reinstalled the PA Performance Alternator and hooked up my SCT to data-log, at least my Voltage was good with the car off and then when running. My battery light is still on, I do suspect there's a wiring/ground/who the hell knows issue somewhere!

I'm going to take it to that Autostart on Monday, and hope they can help me b/c this is just pathetic to deal with.

[00pooterSS]

Auto part store, off the shelf, reman/new alternators are junk. I had 8-10 of them fail back to back (lost count) in roughly 14 months, one literally lasted 5 minutes. I tried them from 4 different suppliers, I tried rebuilt and "new" (all were from parts stores though).

I finally bought a used OEM one for $40 at the junk yard and it lasted until I sold the car over 2 years later, that I know of that alternator is still going 3 years later.

I kept thinking something was wrong with wiring like you are thinking now. But the only thing I changed when my problems started was the alternator, got a used OEM one and never had a problem again.

That was on my camaro though just FYI.

[bjtheman1]

FINALLY! It has been fixed...

The 3-wire harness that clips into the alternator had 1 wire broke, and 1 wire held by 2 single strands from each side. You couldn't see them b/c they were covered/taped/etc.

Everything I went through and it was the damn harness. Now I just have to figure out what happened to my stereo...pops when you turn it on/off now??