2005 EB charging system fault

[unforgiven]

Hello, I've become the new owner of a 2005 Explorer Eddie Bauer with the 4.0 sohc. It's just out of warranty and have a little issue to take care of. When shifting at high rpm (5000+) the message center comes up with a message saying "charging system fault". It only happens at high rpm at the time of shift and the fault clears as soon as the rpms drop. It doesnt latch up any kind of fault that stays on just briefly flashes it across the message display and you hear a chime go off. I had my normal mechanic look at it and he did a quick check of the charging system at idle and said it looked OK. I've turned on the fan on high with the heated seats on and drove around town and it doesnt have any problems keeping up with the electrical demand then. Any one have any ideas before I take it to the dealer on Monday? Thanks a lot for any thing you might think of, it just might save me some money.

 

[Old As Dirt]

Check belt tension.

 

[unforgiven]

I looked at the tension today, the new tensioner is a little different than my '00 it felt ok and looked ok as best I can tell. Would you hear noise if the belt was slipping a little at high rpm? I don't perceive any unusual noises then.

I think I'll go to the parts store and pick up a new belt and put on tomorrow just to be on the safe side. And I'll check the tensioner to make sure it feel good.

 

[unforgiven]

Well I got a new serp belt for my X today to see if that would fix the charging fault, but it didn't work. I took the alternator off and took it to Advance auto to have it tested it nearly pegged the 150 amp scale, so I guess the alternator is good.

I hooked my volt meter up to the cigarette lighter and drove it down the road. What I noticed was at rpms below 3k it had a nice 14.4V output, when the RPM went above 3k the voltage fell off quickly to below 13 volts just when the check charging system message flashes up.

Any ideas

 

[valiantski]

That happened to me with my F-150 and it was the alternator.

 

[unforgiven]

In case anybody was curious it turned out to be the alternator. I'm back to enjoying my new Explorer.

 

[AuroraExplorer]

I took my 2005 XLT to the dealer because the check charging system light was going on. He said there was nothing wrong and battery was charging- probably the cold weather. He said after it sat inside at service the problem stopped. As soon as I left I got the message again. I called the dealer and he told me to bring it back. It must be something else...then he rattled off a price for an onboard computer...

So I started researching online, followed these posts and checked the acceleration and, sure enough, the check charging system light and that annoying dinging comes on and of at 2000 rpm and stays on steadily around 3000 rpm and up.

So much for the dealer.

Does anyone know what it should cost to have the alternator replaced by a mechanic? My Truck will not be returning to the dealer........:wavey:

 

[crash594]

Save some money and do it your self. I did mine in the parking lot. Remove the belt a couple of wires and bolts. It will cut your cost in half.