REBH 371 Air Conditioners (2 zones) zone 2 not found.

[Leathernek]

2015 FR REBH Fifthwheel with two Dometic AC units, One Dometic CCC2, one furnace.

Thermostat lost zone 2 (which is only for ac units).
1. Used reset, per the user guide, so CCC2 (thermostat) would find all available zones. And ohm checked the zone 2 sensor (it worked). Only zone 1 found

2. disconnected all (a/c and d/c) power for 30 minutes. Then repeated step 1. Still only zone 1 found.

(disconnected power for each of the follow steps).

3. replace circuit board on ac unit number 2 (bed room). repeated step one, only zone 1 found.

4. replaced circuit board in ac unit number 1 (living area). repeated step one, only found zone 1.

5. replaced thermostat, repeated step 1, still only finding zone 1.

6. bought a r11 25 foot (phone wire) connected between ac unit 1 and ac unit 2, by-passing the internally routed r11 comms wire. Repeated step 1, only found zone 1. HOWEVER, when I jumped the r11 cable, ac unit 2 began to run.

Restored air conditioning system to original configuration with the follow:
ac unit 1 has circuit board from ac unit 2
ac unit 2 has new circuit board
new thermostat
original internal r11 cable installed.

system only finds zone 1, system zone one works.
system will not find zone 2.

Any ideas?

[cjtromb]

Try looking at this prior post, not sure if it will help?

[URL="http://www.forestriverforums.com/forums/f28/2017-343rsok-issues-113310.html"]

[Bama Rambler]

2017 343RSOK Issues Here's the link mentioned above made clickable.

Looks like a bad control board combined with frayed wiring in that case.