mustangspotential

Hey guys, recently I encountered my car coming up with a 'Check Charging System' warning with the battery light. It seems to happen during the day or night, randomly, and it doesn't ever stay on, just comes on every so often. I've noticed it happening basically when I have the A/C on for a few minutes or more (lately it's been real hot). Battery gauge reads fine, right in the middle.

I have an aftermarket HU, always using my stereo, and lately been using my A/C. Not sure what's wrong. My car is still under a warranty for a few more weeks. Maybe I'll just call up Ford and have them check it out but I'm not sure what it could be. Anyone else have similar issues? The car has not failed to start since it started doing this and it hasn't even sounded like it failed to start.

Though I'm worried I'll call up Ford, set an appointment, the light doesn't go on and they say there's nothing they can do and that they "checked everything" and it's going to be a waste of my time. Then I'll leave the dealership and the light will go on, lol.

Nuke

The S197's are notorious for having degrading alternators. Do a search and you'll find countless threads on this. They'll often check out fine unless they're bench tested at high loads and even then it can be tough to find. IMO, knowing the chronic issue with the alternators in these cars, I'd make sure the battery load tests good and simply replace the alternator with a PA Performance unit. AM sells them, IIRC.

CMcNam

What Nuke said. I just recently bought a PA alternator to replace mine.

mustangspotential

How do I prove the alternator's no good to Ford though? They're not going to want to replace it under warranty, especially if the CEL isn't on/or the idiot light for the charging system. It has just randomly come on for a minute or two while driving lately.

I am covered for a new alternator under warranty IF it is faulty, so I wouldn't buy the one you're saying just yet (thanks though), unless I needed to because I had no warranty.

But I had the battery/system checked today at Autozone. The battery read 12.7V, 100% charging when off. When started, it was a little over 14V, and it said Battery good, Diodes good, System good, etc.

A little confused maybe. Is it possible with the A/C on max, radio blasting etc that the battery got temporarily overloaded and that's what produced the idiot light randomly?

Nuke

Assuming the alternator and battery ARE both good, then you shouldn't get any indication unless you're running some heavy duty aftermarket gear. There is always the possibility (and I say this only in hopes to rule this out...) that you have some intermittent issue related to the water leak that plagues the S197's, especially the 05's and 06's.

IMO, I'd foot the bill for the alternator if Ford says no (which they will) since it's simple peace of mind due to the OE charging system crap they give us.

Curious: did you purchase an extended warranty? For the money you paid if you did, you could have bought a lifetime supply of alternators and batteries. Aftermarket warranties are for.... faint of heart (who says I can't be politically correct?).

drewsky

My alternator just went out yesterday. Was the origional from factory, no charging system waring came on even tho it died in the middle of a drive. If you have an aftermarket stereo and it indicating something I would replace it with a higher amp alternator.

mustangspotential

I'm hoping it has nothing to do with the water issues, but it had rained a couple days lately. I do have an aftermarket stereo, this hadn't happened with the Shaker. However, this also hasn't happened in a couple days now and seems to have gone away. And it only really happened when the A/C was on full blast.

I do not have an extended warranty, I more often than not do not believe in that. I have the standard used car warranty that will be up later this month. If something happens before then, I'll bring it to Ford, but I'm sure they'll dick me around unless it's something that has the car unable to start.

Lifter583

+1 I just had a friend go throught the same thing with her GT...light on and off went on for quite a while...she took it to Ford...they load tested it and it eventually failed...the brushes were making bad contact at times...she did have a extended warranty so it was replaced and on her way...

mustangspotential

Reviving this a little bit:

Okay so this hadn't occured for like a week or so after this thread. Seemed like any potential problem was done. But again, when I turned the A/C on, about 10 minutes later it started happening again. So it seems to ONLY happen when the A/C is on, especially if its full blast. Anyone know what the deal is? Or same thing, alternator can't put out the power?

JFitz

Alt is bad. Your battery might be on the way out too, since it takes up the slack every time the alt stops charging. Probably worn brushes that are making bad contact. You'll notice you can tap it with a mallet and it'll start charging.

Now, it could be that the alternator is dying, but isn't dead yet. Under heavy load, it doesn't deliver the correct output and trips the charging light. I believe out voltage gauge is a dummy gauge, just saying it is or isn't getting a charge.

The heavy load could be from your AC needed to be charged with refrigerant. Low refrigerant will overheat and tax the compressor, as well as not cooling as well. Could be that it is low on refrigerant, which drags on the compressor, which drags on the electrical.

maybe. But you should be checking fuses anyway.

So, test your Batt/alt/fuses and charge your AC system. See where that takes you.