Battery light is on. Alternator and battery tested good?!

So a last week my battery light popped on. After 5 minutes of driving it will go on and won't turn off. I had my alternator and battery tested 3 times and they tested good every time. Any ideas? It's driving me crazy

 

Try checking the fuses and grounds? Any code popping up for the check engine light? etc.... any mods etc... more info you tell us the better.

 

I checked the fuse and all seem good. I haven't checked the 120a alternator fuse yet.I don't have any electrical mods. I have no codes. The check light has never came on.

 

who do the battery and alternator testing? don't tell me autozone, pep boys, etc... did it. Those parts changer don't know jack about cars or trucks but try their best to sell you parts you don't need.

 

Yeah man. I don't know anyone else that would do those testing.

 

It probably a bad cable somewhere. I had the ground cable burn in the center. A couple of strands were connected. The battery light was on and all. Battery was tested good. I'd follow the ground and positive cable and check them.

 

your battery is 6 years old. its time for a new one

 

I will definitely check the cables next. Thanx man! And it has a newer battery I assume because when I bought it it had a duralast gold battery.

 

As others have said, bad cable connection or if it has one, bad regulator. I would remove all connections and clean them, including the block. Have you done a load test on the system? You should have ~13.3-13.8 volts at average load while driving.

 

If all they try to do is sell parts, then why did they say the battery and alternator tested good? I have a great group of suppliers from these places.

As to the OP, there have been a couple members who have had problems with the control wire connector. This is the small connector that plugs into the back of the alternator. Check to make sure the wire is not broken. This is the same connector that lets the on-board computer know if the alternator is charging or not, which is what the battery light actually means.

You can use a volt meter to test what the battery is receiving by connecting it to the middle of the posts while the engine is running. Normal voltage with engine running should be around 13.5 to 14 volts.

 

Thanx everyone for all the advice. I really appreciate it. Hopefully I can fix this problem now.

 

Also check for positive and ground cable terminal corrosion and a loose alternator belt. The battery light is lit due to a significant miss match in voltage between the battery and alternator.

 

I finally fixed the dang problem. I changed out the alt-s fuse and cleaned the terminal connectors and the battery light went away and hasn't came back.