MS4448PAE not communicating with ME-RC50 or ME-BMK

I have a MS4448PAE installed with a ME-RC50 and a ME-BMK that will not communicate. I have 14.2 DCV on both cables coming from the inverter to the devices. When I connect the remote, and following the power up self-test, all of the LEDs turn off and “No Inverter
Com” is displayed. Also, when the BMK sense module is powered up the LED ends
up blinking red. I contacted Magnum Tech support and they we not very helpful. Thank you.
Comments
http://www.magnum-dimensions.com/sites/default/files/MagArchive/64-0003-Rev-F-ME-RC_Web.pdf (page 3 for cable)
-Bill
It's a bit surprising (to me at least), a data cable is running 14.2v. I would have expected ~5v, but I don't know much about Magnum networking.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter