Good Evening Barth Family,
Our 1993 Barth Breakaway is giving us an issue with the Chassis Batteries/ Alternator. I went out after one week of the coach sitting, and the chassis batteries were dead. These are brand new batteries. After charging them back up, they were dead a day later. After checking for shorts, here is what I have found. When the key is off, there is a 4 amp draw off of the chassis batteries. There are 2 wires coming out of the top of the alternator. When I unplug that harness, the amp draw goes away. I cannot figure out where these two wires are going. My wiring diagram does not show it, but I could believe it goes to a voltage regulator... just not sure where it is located.

It probably has an internal regulator if the wires plug into the alternator . If so , you may have an problem in the alternator itself . A picture of the alternator would be helpful .

One goes to the battery, the other to the alternator light. check the wires to ground, one should be open the other some resistance through the blub, do the same to the alternator terminals, one should not go to ground, the other through the field, so some resistance. If either goes to ground directly, replace the alternator.

If you are old school like my Nose, I have a volt meter, no light bulb, both go to the battery, but one through the volt meter. So neither should go to ground.

The other wire senses low voltage and tells the regulator it needs to charge the battery.

Here is a picture of the alternator.

It appears to have an internal regulator.
Is the alternator charging when engine is running?
As Duane suggests, those wires are for remote voltage sensing and the gauge/light. There should be little current through them.
It appears there may be an internal short. Points to bad alternator....

I agree , looks to me like it has an internal regulator .
I'm thinking you need a new alternator .

That two wire plug to the alternator needs to have a wire loom where the zip tie is . The vibration will wear through the insulation and short out .

Alternator does not appear to be charging when the coach is running, so yes, I think the alternator itself is the problem. And yes, I do agree that wire needs to have wire loom on it.

Thank you!

Replaced our alternator about a year ago--- the new one did not need those wires---- just the main charging wire and it works just fine. Put those wires up and out of the way so they don't/can't contact anything.

Bud

You can replace the alternator as Bud suggested with a "single wire" alternator BUT if you have a diode battery isolator, (so that chassis and coach batteries can be charged from one alternator with out relays or switches)you will not get a good charging voltage to the batteries as the diode drop of about 0.7-1.0VDC will reduce the effective charge voltage. A voltage sense wire directly from the batteries must be used so the alternator will put out a higher voltage to compensate for the loss in the diode isolator.

Contrary to popular belief Diode isolators can be used and nearly full voltage charge can be gotten so long as the diode isolator is inside the charging loop of the alternator.

a little thread drift..

Battery Drain,

My mechanic advised that a long term battery drain problem was traced back to the radio in the front console..According to an old thread (linked below), there is a draw even the turned off as I guess its wired to the 'hot' side of the fuse panel..I have now disconnected both radios ( AM/FM and CB ) Info only..

Doorman's 2nd post on this page
radio drain...