Dreaded EE code

1. You do NOT need 120 volts for the system to work. Just 12 volts. You have that as you get the EE error
2. YES, COM problem. The FIRST thing you do is connect a GOOD Com Cable to Zone one AT the UPPER board and the wall tstst to the test cable. Since you have Older penguins, the most common problem of EE error is corroded(rust) connections. EACH Penguin has a 2 beige JUMP(union) Phone type junctions from the Control boards. THOSE unions are where the rust forms. They are usually located right in front of the evaporator in the return air space and that air is moist hence they get corroded after years of use. Access those 4 (2 on front ac and 2 on rear AC), and you will probably find your problem.
3. LAST, I assume you built your new COM cables correctly? They are NOT Phone cables. COM cables are wired in reverse, if you used PHONE prebuilt cables that is your problem. Doug

Thanks for the reply Doug! Both board's are new and the same result as with the old boards. I take it the unions you are talking about are the p1 and p2 jacks on the control board? If so they are new and clean. You do mention beige in color mine are black. I did make my own cables and checked the wiring 4 times and it is correct to the wiring diagram. Also checked with a cable tester and all reads good. I'm stumped. I have a 2005 Monaco Diplomat.

Inline Coupler
I think this is what Doug is referring to. This is 4 wire but they make a 6 wire that you may need.

I will have to look closer. It looked like my communication Cable plugs directly to board without union.

Stevec4s wrote:
I will have to look closer. It looked like my communication Cable plugs directly to board without union.

Is your Control board in a 8 by 8 inch Galvanized Box? Right in front of the Evaporator? This is important. Depending on the AGE of the penguin determines WHERE the Control board is located. If the control board is MOUNTED and accessed from the TOP of the RV under a flat metal plate that has 2 screws, you will see 2 black 4 wire Com cables connected to the Control Board. THOSE black cables(about 18 inches long) go into the Evap area and have those splice unions that connect to the cable from the wall tstat and then go from the other to the rear Zone 2. ALWAYS disconnect the Rear Zone 2 from the Rear control board at those splice connectors. As I stated, you need to make another Com cable 2 or 3 feet long and do on top and connect the wall tstat direct to Zone 1 Control board with the other Com cables disconnected. Doug

You just joined. It is extremely important that when you post for help, you also post Year/Brand/Model RV. Brand/Model of appliance. Doug

I checked today. No unions. My board is accessed from underside of roof. It is an 8x8 box. I made another cable and unplugged p2 going to the rear unit. Same results. It does sound like a relay click sound on about every six times I try to reset. Here is a link to the photos I took of my cable and test as well as the unit. https://www.dropbox.com/sh/sdtpmld5z83tac7/AACx3RmLNwbn6QBylHc-1GTFa?dl=0

Look at pics 6 and 7 on page 8. Doug

http://bryantrv.com/docs2/docs/operating/Installation_CCC2%20with%20separate%20control%20box_3312792.017.pdf

Update! I was able to get communication. I kept hearing clicking sound from control box about every six times resetting. I decided to plug thermostat in P2 plug, same clicking sound then plugged back into P1 and thermostat starting working. I have no idea why. Problem now is it will not see zone 1. Zone 2 works properly with furnace, ac and heat pump. No zone 1 as an option now. I really appreciate the help so far.

The pics you supplied. WHICH zone control board are you showing? Do you have 2 furnaces or 1 furnace? Doug