High Vdc error on fridge. 19 Volts dc to the power board.

I have a Norcold N621 fridge. The other day I noticed an "E" on my display. This fault is "hi Volts dc". I followed the manufactures instructions and tested the voltage at the fridges power board. I got a 17.9 volt reading (should be 12 Vdc-15.4 Vdc). I then pulled the wires off of the power board and tested the voltage from the wires. I got 19 Volts dc. This is as far as I have gone. To me I have too many volts coming from (?????) the battery or converter. This is where I am not sure how the fridges dc wires come from. I am unsure if the wires are getting dc voltage from the converter or battery, but the battery tests out at 13.4 volts so I suspect the converter. Originally I thought is was the fridges power board, but now I think its the voltage supplied to the power board.

Any thoughts or suggestions?

BTW, this is a 2000 Sportsmen 5th wheel RV.

Thanks