The past couple days I've noticed my charge & abs lights flashing intermittently. Today was more consistent than yesterday.
I don't have a voltmeter to test different points at the moment so I'm just kind of spit balling for now. However, I do have a PFC so I changed the screen so I could watch the volts.
Car starts fine with no problems. PFC reads 11.9-12 volts. If I turn on the a/c the volts drop down to 11.5 and the charge & abs lights come on. If I roll down both windows, voltage drops to 11.6 & lights on again. If I turn the a/c off the volts will go back up to 11.9/12 after a few minutes. If I hit the brakes, same thing, voltage drops to 11.6 & lights back on. Wait a few minutes and the voltage is back up and everything is ok.
I checked the belt and tension appears to be good. I've got the battery on charge at the moment. Battery is new, has less than 500 miles on it. It is a 35R battery. I'm not running any crazy audio system, just an aftermarket headunit.

What should my voltage reading be on my pfc when idling? I couldn't find an idle voltage in the manual. I'm sure it is there, I just couldn't find it in my searching. Should the voltage drop .5-.6 volts when running the a/c, hitting the brakes, rolling down the windows?

Thanks!

 

alternator

 

I'd get the alternator tested, as the alternator should be putting out greater than 12v while the engine is running, more to the tune of 13.5-14. All of those things you mentioned will cause the volts to drop, and .5-.6 volts sounds correct, but it's more noticeable since your alternator isn't pushing enough voltage to begin with. Also, it couldn't hurt to check your grounds while you're at it.

 

exactly what Kenseto said, get the alternator tested, should be putting out close to 14V

 

Took the alternator to advance auto parts to get tested. The machine said that the alternator was good.

 

Check your grounds, and check the big fat output wire from the alternator to the fuse box.

 

I think you have a bad diode in your alternator. If normal is 13.5 to14 v then one bad diode would take you down to 11.66 or 11.16v. So your abs and charge lights would start to light up.

 

Not sure what the deal is, but today I drove it to work and my voltage was steady above 13.

 

Mine did the same thing when it went bad, would work for bit then crap out.

 

Either that or I fixed a gremlin by unistalling / reinstalling it

 

Put a wrench on the alternator pulley bolt and make sure it isn't slipping. My catch can once got a little too full, and sprayed a little oil on the belts. It wasn't enough oil to be visible, but it was slipping.

You may not have a catch can, but FDs are well known for holding their oil.