No Power to the Dometic 10 button CCC

[newmarokie]

First, my air conditioners are not working! I have done all the resets, but my CCC is not lighting up. The fuse in the mid bath marked HVAC controls is good. Is there another fuse I need to locate before I go into captain destructo mode?

 

[Neal]

Try powering off the salesman switch at the door for a minute, then back on. I realize the AC's require 120V (short power) but something with your T-STAT sounds like an issue. You can also try taking it off the wall, disconnect/reconnect it. I don't know if yours goes through KiB or something else that could be an issue in the line.

 

[TheLooks]

There are a couple of things that can be. If you have the original manuals for it look thru the instructions. It needs 12v to operate so low voltage (blade) fuses. Don't trust looking at a fuse, and don't trust the led lights in the fuse box. Find the fuse and pull it and visually inspect and ohm it out. The problem can be in the thermostat or the control box up in the AC unit. It will most likely require a multimeter to track down the error.

 

[TheLooks]

See this, but it doesn't tell you where the 12v supply comes from.
General Troubleshooting: If the display is blank, check the 12V DC fuse in your RV’s fuse panel and ensure the converter is on or batteries are charged. For unresponsive controls, perform a soft reset by turning the thermostat off, waiting 10 seconds, and turning it back on. If buttons are physically stuck or unresponsive, clean the internal contacts with spray contact cleaner or replace the switch assembly.

 

[Chuggs]

Your Penguin II gets power to red and black wires on terminal P6 on the control board. It’s a 6-pin connector. I believe F16 fuse in half bath is power. This entire fuse panel is only powered when the salesman switch is ON connecting the house bank power to the panel, and other “disconnect battery powered” panels and breakers.

From the control panel, a 4 wire phone Jack looking connection goes to the CCC2 thermostat and provides it with power. In most installations, there are two of these jacks. They daisy chain. On our coach, Thermostat >>> Front A/C >>> Rear A/C >>> basement Dometic control box linked to ME-AGS-N (Auto Gen Start) .

If the saleman switch is ON, power is getting g to fuse panel and fuse is good, P6 terminal connections are good (check for 12v on the red and black), the phone wires are connected to the control board and the rear of the thermostat…you should be good.

 

[TheLooks]

But it is not a common phone cable. It is wired differently.

 

[Chuggs]

But it is not a common phone cable. It is wired differently.

“Looks like”. The orientation of the Jack is flipped. Technically an RJ11 if it’s 4C6P or RJ12 if it’s 6C6P. Didn’t expect that the wire would need to be replaced.

 

[Kevin D Pem]

There are a couple of things that can be. If you have the original manuals for it look thru the instructions. It needs 12v to operate so low voltage (blade) fuses. Don't trust looking at a fuse, and don't trust the led lights in the fuse box. Find the fuse and pull it and visually inspect and ohm it out. The problem can be in the thermostat or the control box up in the AC unit. It will most likely require a multimeter to track down the error.

Wow. Didn't expect that about the indicator LEDs. Here is a little tip about blade fuses. There is an opening for testing the fuse without removing the fuse on it's top. Every time you remove a fuse the life expectancy of the spade connector holding the fuse is reduced.

 

[TheLooks]

I have had to replace the wire twice and replace the plugs on the ends a few times when they were to far gone.

 

[stang37]

The box circled in this picture is known to go bad due to moisture. A friend an I worked on his Ac unit half way across the US. His 10 button CCC2 wasn't getting power. We tried new wiring, new thermostat, new control board all didn't fix the issue. Finally a tech told us to get new connection blocks. That resolved the problem. I think he got them off Amazon.

 

[TheLooks]

This is true, but there are 2 different "boxes" to get. one is a pass thru, and one reverses the wires.. They are not marked as to what is what.

 

[newmarokie]

Here's is an update. I spent some time with Dometic on the phone. I had already decided my unit was probably bad so I dropped $1700 on a new Freshjet5. Drop in replacement, yeah right. Yes when you drop it, it fits the hole and the bolts line up. Ya know in reality it is a Penguin II. The only changes I can see is they have moved the capacitors over on the other side by the compressor and moved the control box to the front of the unit. Oh, and the cable change. The problem with the control box move is that there is no access to the control box without unbolting the unit and breaking the seal so the roof. The unit is working in that it is cooling, but with 0 control. It is "piggybacking off of the back unit. More to come.......

 

[newmarokie]

I have been traveling with work and just got home. I am going to switch the two communication cables tomorrow and see if that resolves the piggybacking