Charging System Light was coming on intermittently now it's coming on everyday. on 2005 Ford Explorer

My husband had changed the EGR valve on our 2005 Ford Explorer and after that the charging system light would come on every once and a while and then go off. My husband changed the spark plugs this past weekend and now it is coming on every single day constantly and is very annoying. Battery and Alternator are fine because I had them checked. All the gauges on my instrument panel read normal. What is causing this malfunction and what can I do to fix it? Please help!!!

by in Reidsville, NC on September 12, 2013
2 answers
ANSWER by on September 12, 2013
check for loose connection at alternator you could have a bad regulater.if thats the case you will need a new alternator.check to see what the alternator is charging it shoud be batween 13.8 v and 14.2v
ANSWER by on September 13, 2013
AGREE WITH GOODGUY BUT POSS ALT IS GOING OUT