Q: check charging system on 2005 Ford Explorer

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My check charging system warning keeps beeping at me. I bought the truck used in April 2008, within the first week had to replace the battery; April 2009 had to replace the alternator; Auguest 2010 replaced battery again. Replaced all belts March 2011. So far nothing is making the warning beeps go away. There seems to be no rhym or reason for when it goes of. It is happening now everytime I drive the truck and stays on more often. The indicator for the battery on the gages doesn't move. Not sure what the problem is or how to get it fix and don't want to keep replacing alternators and batteries.
(1) Answer
Check charging system is a result of a problern with the alternator and/or the wiring connector to the alternator. Not very complex - I would verify all connections first - check the rectifier connector at the alternator. Then, perform a test of peak amperage and voltage. This will clearly show what is not functioning properly.

Good luck.