I'm looking for a suspected bad ground connection on my 2002 with 4.6. I've been battling a battery light for a while it Goe away and then comes back and have been thru a lot of fuses the last few months too. There's a lot going on with this truck as far as worn out and repaired and modified but I've got lean fuel codes now and have replaced hoses and Cleaned tb an iac is new. I've still got vacuum leaks to fix on some injectors and I believe some gaskets but I've bought new 02sensors and maf sensor but would like to know for sure that I'm replacing bad parts before I waste money on something that I mightve tested wrong or diagnosed wrong. I'd like to know more about the vehicles main grounding points and how to test and find a bad connection and see if I've missed and bases on ho to trouble shoot

 

Just google "How to Diagnose Automotive Electrical Ground Issues" (without quotes)

You'll need to refer to yourvehicle electrical schematics for all the grounding points

 

There's nothing in your post that indicates you have a "ground problem".

 

It sounds like an alternator problem. Get both your alternator and battery tested at your local parts store.