The last couple of days I've been getting a random red battery light come on then go off. Then sometimes flicker a little. Then stop. Then not come back on for the rest of the day.

I went and had the battery tested while in the truck. It had 12.6 standing voltage. Alt was putting out 14.6. But the 750cca battery was only showing 533 cca, replace battery. Well I don't trust those machines. I was hoping it was just corroded cables.

The battery cables were badly corroded. I cleaned them up real good and thought I had it fixed. But it just did it again. The battery light will not come on and stay. I just checked it and my readings were the same as before.

You guys think it is in fact the battery? Or could the alt be on the way out. It's about 2 years old if that.

Any idea's? Thanks

 

When my 08 had a random flickering battery light, I replaced the alt and all was well. For me, if the battery is 3 years old, its gone! JMO. Have them both tested will be the clear recommendation.

 

O reillys tested both while the battery still in the truck. Are you saying remove battery and alt and have tested? The truck is my only means of transportation. If I remove them no way to get there,,,lol.

 

Corrosion can go down into the cables. Not sure what "badly corroded" means to everyone but it might still be the cables, since the bat. and alt. tested okay.

Here's an overview of causes and solutions.

https://www.700r4transmissionhq.com/...battery-light/

 

Run test leads into the cabin and drive the truck to see if voltage drops at any time.
Had a Maxima, drove me nuts as everything would check out, but eventually found the problem,
when voltage dropped, checked the system, bad connection at the plug in terminal on the alternator.

 

All good advice above IMO
If you see no connection or cable issues, replace the alternator

 

Check the Alts inline fuse holder if it has one (you didn't mention the year). Ford had a problem with the trucks that had the holders, the fuse would dislodge inside holder and short when hitting a bump in the road. Battery light may illuminate of flicker when it occurred.

 

It's the 03 in my sig.

I'll look for the fuse holder. But the light was flickering just sitting in my driveway. I guess I need someone sitting inside watching the light while I move wires around maybe?

 

Is this the original alt?

 

Changed less than 2 years ago.