I have a 2005 Taurus. I had the battery replaced at the dealer in late November after a charging system check showed it was weak. In late December the check charging system message came on. Approx 600 miles after the battery was replaced. I checked battery voltage at the battery and it was 11.1 V. I had the alternator replaced at the dealer last week.Since then the charging message comes on and goes off after 30sec. This is random. The voltage at battery is 14.6V at low idle and high idle. I had the dealer recheck and they say charging system is fine. I think the charging voltae is on the high side. I think the regulator is either the wrong one or intermittent. This is a rebuilt alternator.Opinions?
Experienced something similar. Turned out it was a $10 diode on the bottom of the fuse box per the mechanic. This was after I bought a new battery, pulled the alternator and had it tested, and checked every wire. Hope this helps.