12 volt system

[Roger L.]

Morning Everyone, So here's my new issue, I'm driving my 2006 coach down I-94 to Camping World for some maintenance work, and all of a sudden the alarm goes off telling me that the alternator is putting out 15.7 volts and that it's over charging the batteries.
I made it Camping World and asked them to look into this new issue. They told me that they were not able to work on this and that I had to take it to a chassis shop.
Any Ideas on what this could be? Bad relay maybe?
Seems like it's always something.
Thanks in advance
Roger

[lonestarace]

It could be a bad voltage regulator in the alternator, which requires its removal and rebuild or exchange for a new or rebuilt one.

[GMDavidson]

I vote for the regulator in the Alternator also, but I would check the alternator voltage output independently, with a voltmerter, to see if it agrees with your alarm voltage. If it does, then a bad alternator regulator.

[wa8yxm]

It might be a GM/Workhorse chassis.. GM sets it's alternators to what I personally consider too high a voltage and I think 15.x is it (without metering)

Is that alarm a "Stock" or an after market device?

NOTE: in my coach there is a power strip (A West Mountain Radio "Rig-Runner" and it has over/under voltage alarms.. Every time I use the turn signals the blasted over voltage alarm would beep at me.. Most annoying. I finally disabled it.. The GM alternator issue is the cause.. it runs right at the trip point.

I-94 toward CW.. Belleview, MI?

I am in Davison just now.. Farmington HIlls come the weekend.

[Algoma]

I agree that it's the internal voltage regulator in the alternator, unless the alarm has failed. Easy for anyone with a voltmeter to check.

[lllkrob]

All automotive type 12v alternators are designed to charge @ 13.8v to 14.2v. If it is in fact charging at 15.7 volts one or more diodes in the solid state regulator bridge is bad. Time for a exchange alternator. This is not a owner serviceable type repair unless you really know what you are doing.

[Roger L.]

Good Morning Everyone, Here's an update on the alternator problem I'm having.

Well after having my motorhome for more than 45 days, Camping World finally got back to me and stated that they put a meter on the alternator and it was find. The alternator was charging at 13.4 volts. Go figure? Do you think I should just go buy a new alternator and replace it?

[EngineerMike]

Chassis voltage reads out on the LCD screen in the Actia speedometer to a tenth of a volt. I assume this is where you were reading the 15.7, or was that on the Silverleaf? I'd check that at the alternator before leaving the parking lot, & then drive it and watch that number.
Then before getting too far, I'd find an alternator shop that can bench test yours, pull the original and have it tested by somebody w/real test equipment.

[Wil Rathke]

This seems to be an intermittent problem if all is well now. The following is a shot in the dark before replacing the alternator.

If the monitor panel was reading 15.7 volts, this could be the open circuit voltage of the alternator without the chassis battery connected.

I suggest that you do a visual inspection of the chassis battery connections. If there is any corrosion, turn off both disconnect switches and remove the ground cable first and then clean the chassis battery and cables to bright metal.

[mythplaced]

Quote:

Originally Posted by Roger L. ....., Camping World finally got back to me and stated that they put a meter on the alternator and it was find. The alternator was charging at 13.4 volts. Go figure? Do you think I should just go buy a new alternator and replace it?

I would NOT trust Camping world....

Go to a REAL shop and get it checked before you fry your batteries (or worse)