Check Charging System

As I was driving home last night, the "check charging system" message popped up in the cluster. I recently installed a new alternator and the battery is less than 1 year old. My radar detector is showing the voltage between 11.7-12.1. It used to be mid 14's, prior to last night. I checked all of the connections and fuse 43 which look fine. Any ideas? I am hoping my new alternator didn't crap out on me.

If the car is running and you check the voltage with a multimeter, and it's running at 12v or less, then it sure sounds like the alternator quit to me.

I had this happen about two months ago, bad alternator

Looks like the alternator. I tested it with a Midtronics Battery/Alternator testor. The test only showed 11.97 volts.

Make sure when you buy a replacement to ask for the updated part number, I wished I saved my box for the new number but they had to use it to send my old back. This was from a ford dealer. Knock on wood, this one is acting right.

max2000jp said:

As I was driving home last night, the "check charging system" message popped up in the cluster. I recently installed a new alternator and the battery is less than 1 year old. My radar detector is showing the voltage between 11.7-12.1. It used to be mid 14's, prior to last night. I checked all of the connections and fuse 43 which look fine. Any ideas? I am hoping my new alternator didn't crap out on me.

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welcome to my world bro. it sucks.

Check all your connections. Could be something loose and the alt is fine.

I'm on my 4th alternator this year since April. The new alternator is no longer available through Ford. All the replacements now are rebuilt.

07 Boss said:

I'm on my 4th alternator this year since April. The new alternator is no longer available through Ford. All the replacements now are rebuilt.

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4th this year? WTF ?

well dont feel bad for using rebuilts cause mine fried a PA in 1 week.

wtf is going on with this cars? some dont have problems and the others are just eating alts

This is starting to make me mad. The replacement alternator was only charging at 11.7 volts. I just replaced it with another remanufacturer NAPA alternator and it started and was at 14.4 volts. I drove down the street and the power cut out. The alternator is overcharging the system. Any ideas? My mechanic thinks it's the reman company not knowing how to rebuild these things.

Just want to give some info from my experience. Get rid of the clutch style ALT pulley if you haven't already done so. I have found that they wear out over time and can actually destroy your alternator by making them work harder than the need too as they begin to slip. A lot of times you have to transfer the old pulley aver to the new ALT having the same thing happen again. Not saying this is "for sure" anyones issue. I just find it nut's that folks are going through 3-4 alts. a year.

You may want to invest an a PA alternator if you have tried a traditional pulley without success.

And yes, the ALT's on the 3 valves suck! Very temperamental electrical system.

Edit: I advise against using Napa alternators as well (especially the low line). I deal with them a lot at work and I have a lot come back and some don't even make it out of the shop. 13.8-14.2v is normal.

Where is the best place to buy a PA alternator?

max2000jp said:

Where is the best place to buy a PA alternator?

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you should check your entire electrical system, cause I also thought my problem was only a faulty alt, bought the 130 PA alt and got fried in 10 days.

max2000jp said:

Where is the best place to buy a PA alternator?

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Post on the Vendor forum. I'm sure you can get a decent price from one of our vendors.

MexGT said:

you should check your entire electrical system, cause I also thought my problem was only a faulty alt, bought the 130 PA alt and got fried in 10 days.

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What was your issue? What did you check?

max2000jp said:

What was your issue? What did you check?

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havent checked a thing yet, I dont feel like even looking at the car ATM. so pissed.

MexGT said:

havent checked a thing yet, I dont feel like even looking at the car ATM. so pissed.

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I think I've got bad luck and it's the alternator:

OEM Alternator: At 78K, I got the infamous P0340 code. I replaced the alternator

Reman Alternator 1: Drove it for two weeks and then I got a Check Charging System message. The voltage was at 11.7.

Reman Alternator 2: Installed it and it was putting out 14.4 at idle. I drove down the street and once I hit ~2,700 rpms the voltage would keep climbing and the car would cut the power. The lights, gauges, dash, etc. would shut down momentarily

If you have a good alternator, but are experiencing low voltage issues, check your fuses, ground and positive cables that run between your alternator, fuse box, battery and starter. I've seen some cables get too close to a set of long tube headers and get heat damage causing them to act as a resistor and not carry the full voltage from the alternator. Check your ground connections too. If the new or remanufactured alternators are going bad within a short period of time, something is causing them to fail. Perhaps this will help troubleshoot an underlying problem. Ensure your cables are 4 gauge. I've seen some shops do modifications and then splice in smaller gauge cables.

Gray Ghost GT said:

If you have a good alternator, but are experiencing low voltage issues, check your fuses, ground and positive cables that run between your alternator, fuse box, battery and starter. I've seen some cables get too close to a set of long tube headers and get heat damage causing them to act as a resistor and not carry the full voltage from the alternator. Check your ground connections too. If the new or remanufactured alternators are going bad within a short period of time, something is causing them to fail. Perhaps this will help troubleshoot an underlying problem. Ensure your cables are 4 gauge. I've seen some shops do modifications and then splice in smaller gauge cables.

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I checked Fuse 43 and it looks good. The harness that runs from the battery to the alternator also looked good.

Alternator Problems

My "Check Charging System" indicator went on too and had the alternator checked and it was good...

So I checked the small wiring loom which was wrapped in the black electrical tape and attached to the alternator...

Because I had done some engine work and moved the alternator out of the way without disconnecting the wiring, one of the small wires inside the cluster of wires attached to the alternator came loose...

I had to unwrap the black electrical taped wiring and sure emough, there was a broken wire inside it...

Repaired the wire and ALL IS WELL AGAIN!!!

Try this first before you buy a new alternator...

Dave