I have been trying find out why my battery light on my cluster is staying on in my 1987 F-150. After starting my truck the light will go off for a few seconds then come back on and stay on.

At times I have noticed the light flicker between going off and staying on.

Truck has a new alternator and I just done the Big 3 upgrade on the positive, negative, and starter wires along with adding a couple of new ground wires with the extra wire I had left over from the upgrade.

Any ideas on where to start trouble shooting this problem?

 

How old is your battery?
Make sure the connector on the alternator is home and tight, check connector for corrosion.
Same with all connections.
Since its flickering and you just did some work, I would suggest the problem lies there somewhere.

 

Battery is about a year old.

The battery light was on before I did any of the work. I replaced those parts for upgrading reason and not because they went bad or trying to get rid of this light.

What is the purpose of the battery warning light?
What am I suppose to check when it comes on if the light is working correctly?

 

Check for proper voltage at the battery, about 14.5 running. The light tells you the alternator isn't charging, but you might just have a short. The alternator plugs do go bad and they have them on the shelf at the parts store. I went through two on my '87. I think the white wire on my plug melted which made the light come on.