All was great when I went to TGO on Thursday. But when I returned I started to get an over and under voltage problem again.

I am still having problems with my Chassis voltage output.

Here is what I am experiencing:

When I start the bus the voltage meter reads out at around 28.2 volts.

Once I warm up the bus for a few minutes it is still ok.

The second I hit the Air Parking Brake the voltage runs up to about 30.5 and I get an over voltage. It also happens when I use the Jake Brake, but not when I turn on lights, or dash air conditioner. It appears to be isolated to the brakes. (My last visit to Prevost Car Dec. 4, 2008 they reset my ABS system which showed an over voltage)

Here is where it gets tricky: If I turn on the genset the voltage drops from 28.2 to 25.5 and stays there unless I use the Jake Brake in which case the voltage will swing up to around 30.5 wildly and then back down.,

1. Question: How is it possible to have the genset that is providing energy to the house side effect the chassis side:

Here is what the Service manager at Marathon Florida told me to do, which I did: John is a great guy and really helpful.

John (Marathon) Said to Do: The generator powers the inverters in charging the "house batteries" not
the engine batteries, the only thing in common would be the "jump start"
relay stuck on. This would allow the engine alternator to stop charging
causing the light to come on at the dash.
To test this turn off shore and generator power.
Check voltage at the chassis batteries.
Turn on house or generator power.
Check voltage at the chassis batteries and see if it increased.
Jump start solenoid is usually mounted above the engine batteries, check
both sides for voltage should be different. If the same solenoid stuck,
turn off house 12 and 24 volt house disconnect switches for 20 seconds
then turn them back on and recheck voltage.

2. Question: What possible relationship is there between the Jake Brake, Parking brake, and the ABS system, could there be a short to ground somewhere, maybe in the ABS system??? Have no clue but need to sort this out as the voltage swing is not good for the equipment.

PS> I have replaced the Voltage regulator, it is new. I am also replacing tomorrow the Vanner Monitor EM70A the little one that monitors input, balance etc, as I am also experiencing a balance issue as well, but only from time to time.

Love some ideas on this one.

Thanks,

Bruce