WHEN I START MY 2005 U270COACH, THE VOLTAGE READOUT ON THE XANTREX MONITOR NEXT TO THE MICROWAVE QUICKLY CLIMBS TO OVER 16 VOLTS. WHEN I GO TO THE HOUSE BATTERY COMPARTMENT, THE BATTERIES ARE STARTING TO OVERHEAT. BECAUSE I DON'T KNOW HOW TO FIX THIS PROBLEM, WHEN I NEED TO DRIVE, I START THE COACH AND QUICKLY DISCONNECT THE NEGATIVE TERMINALS ON THE HOUSE BATTERIES.
WHEN I ARRIVE AT MY DESTINATION, I SHUT OFF THE COACH, RECONNECT THE BATTERIES, AND PLUG INTO SHORE POWER. EVERYTHING WORKS FINE WHEN PLUGGED INTO SHORE POWER.
I NOW BELIEVE IT IS POSSIBLE IT IS THE VOLTAGE SPIKES THAT CAUSED MY HWH SYSTEM, AND BLAUPUNKT REAR VIEW CAMERA AND TANK MONITOR TO GO OUT.
ANY ADVICE ON HOW I SHOULD TRY TO SOLVE THE HIGH VOLTAGE PROBLEM?
THANK YOU IN ADVANCE
You need to look at the sense wire from the alternator all the way to the breaker that the wire goes to. The wire could be broken or corroded at the terminals. Your voltage regulator on your alternator needs to be checked as it may have failed. This would be the first two things I would check.
Pamela & Mike
Welcome cdminccm to the Forum. NO NEED TO SHOUT! We will help you figure it out.
Follow Mike's suggestions - see what you find. Until you get it sorted, drive as little as possible. That high voltage isn't doing your start batteries any good, either.
If you DO need to travel before the problem is fixed, suggest disabling the alternator by removing the "excite" wire. Tape the end of the wire to avoid a short. Then, run your generator and engage your "BOOST" switch. The generator will keep both battery sets charged whilst on the road.
Let us know what you find.
One other comment
Yes this high voltage (16+) is most likely what killed the electronics that you mentioned.
Pamela & Mike
Had a similar problem the isolator was bad
If you are not clear on where to find the "sense wire" and the "excite" wire, try reading the concurrent thread linked below. It contains a diagram of a 2003 alternator. Hopefully, the connections are similar to yours. Diagram reproduced below. Red arrow points to "sense wire", green arrow points to "excite" wire.
Alternator trouble (http://www.foreforums.com/index.php?topic=31109.0)
@Pamela & Mike Mike, is that breaker on the sense wire auto reset, or manual reset, or "blow and replace"?
The breaker is/should be auto reset.
Seems like we posted a part number for it and the size a while back. I will post a link as soon as I find it.
Pamela & Mike
On edit: the numbers we posted are for the breakers behind the front kick panel and do not have the mounting tab.
We had this same problem. We
1) replaced the sense wire, didn't fix it
2) checked the voltage regulator, didn't fix it
3) replaced the isolator, problem solved
Good luck
You could safely disable the alternator by removing the excite wire, which is connected to one of the two small terminals on the alternator (the other small terminal is the sense wire).
Be sure to tape up the excite terminator so it does not touch ground which would be a direct short.
Disconnecting the output wire (heavy gauge ) of the alternator would leave the alternator producing high voltage with no load and I am not sure what that would do.
Had the same problem, removed belt that ran alternator, started generator [make sure inverter/charger is in charge mode] closed boost switch and drove another 500 miles till I found a place to troubleshoot. Inverter will keep both sets of batteries charged.
Not sure of ISL setup, but make sure belt only drives alternator, or alternator and ac compressor.
Seeing you are running generator anyway, you can use roof ac's if nec.
Excellent idea! Better, and easier, than my suggestion. This is why I love this Forum - many brains pondering the problem!
(Edited my earlier post to avoid confusing the OP)
Any of us that have a problem with over charging need to keep an eye on the water
levels in the batteries. Over charging boils the water out and will burn up a battery
fairly quickly.
Carter-