high voltage problem

[rpowell]

I have a 2010 Berkshire 390BH. It sometimes shows high voltage on the dash pannel. You can race engine an it goes back to normal with no other problems. This happens sometime and not others. After engine has warmed up no problems. Dont know where to start alternator or batteries. Does the inverter play a part. Thanks for any info.

[sherdep]

what engine package do you have?
Gas or Diesel?

[LadyWindrider]

My first guess would be the alternator, since it has a built in voltage regulator. The batteries would be my last guess. The voltage regulator is to control the charge rate and voltage, so that is to blame. The other guess would be a faulty dash panel. Only way to tell for sure is put a voltmeter across the battery terminals, start her up, and hope the dash panel shows high voltage. Read the external meter, and see if the dash panel is correct. By the way, normal voltage with the engine running, between 13.5 and 14.8 volts.

[rpowell]

Thanks for the reply. I have the ISB Cummins