One other (and very simple) thing to check - the neg connection to the battery. My GF's 2001 Cherokee had a bad connection at the negative terminal (couldn't be clamped down tight enough on the battery post), and it gave me an overcharging reading (pinned at 21v or whatever is top) while 300 miles away from home. Was nothing more than a bad connection, but had me wondering if I was about to burn out the headlights and ended up calling AAA when it wouldn't crank again at a gas stop before I figured out what the problem was.

97tj, Shaved Ford 9 rear, 4:10's, New 35x12.5 BFG KM2's to test!, Warn x8000i, ARB's, Quick Disco's, Hand Throttle, & it's my DD. smile