Working on it between activities here in Key West.  Also having to fix basement door that opens by itself and AC that sounds like a jackhammer so not much progress.

 Board is 2 sided AC Neutrals  both in and out are  connected at J6&J7. The actual connection is cone in the relay center left. The actual connection seems to be initiated by connector 4 and three in the 4 wire molex. I can't trace how the signal gets from the 6 wire harness to the 4 wire one to actuate though.  I would need to connect AC and DC to it  to find out more and I don't have the power supplies here to do it safely. The most recent board that I remived had evidence of heating on the C5 capacitor but the other old ones have no visual evidence of a any blown components.

One problem in troubleshooting the circuit boards is a lack of schematic for them. I know of no source for circuit board schematics. I have often wished that I could find one. 

Am I correct that your refrigerator never automatically selects 120V? That seems to be the reason you don't get electric operation. If you had not replaced the main circuit board, I'd suggest that but, unless something is damaging them it seems very unlikely to be the issue. Let me check to see if I can find someone who works in RV repairs to help you.

  On 10/22/2019 at 11:56 PM, Kirk W said:

One problem in troubleshooting the circuit boards is a lack of schematic for them. I know of no source for circuit board schematics. I have often wished that I could find one. 

Am I correct that your refrigerator never automatically selects 120V? That seems to be the reason you don't get electric operation. If you had not replaced the main circuit board, I'd suggest that but, unless something is damaging them it seems very unlikely to be the issue. Let me check to see if I can find someone who works in RV repairs to help you.

That is so true! I have been unable to find one myself.  I have replaced the board three times so either the board id not the problem or something blows up the boards. I would love that.  Thanks.

PS No hurry I am in Key west for fantasy Fest till Monday and won't get much done anyway. ?

Take a look at Dinosaur Electronics.  They have troubleshooting guides on their website and make superior replacement circuit boards if you decide you need another one.

Hi. Sorry to be away for a while but we were in Key West for a festival and I didn't have time or tools to do much. Then I caught a foul nasty cold! Today I got back at it in spite of the cold. I went around the board checking every connection coming off of it to be sure that they went to the right place and that they worked. I also tested the Thermostat just to be sure. All were provably good except for the J3 which goes inside the back of the fridge and powers the fans and 2 heating coils. The fans work. The others could be the door heaters.  They did work. . The other is J 12 which is the ground for a Lamp. When J12 is disconnected the light stays on. It seems like there are several things on the same circuit, each with  it's own ground.  Sloppy engineering but not the problem. I also had the DW stay inside and worked the controls while I  checked the wires where they entered the romex connectors. They did work properly. The pins and sockets all looked good on the connectors also.

 In the end I gave in and swapped out the lower board for a new one I had. There is no change.  It did not fix it.

Tomorrow I will call Dinosaur and Dometic.  Other than that I don't know what to try. I am currently running it on electric when needed by jumping the heaters directly to the AC inputs but that won't work when I am not in 86f weather because the fridge will freeze.

 Interestingly I should mention that that fridge used to work terribly. Never got below 38 and was often in the upper 40's in the day. Opening the door caused a rise of 2-3 degrees which took hours to come back. Since I have run it for 2 weeks straight it has gradually improves to where it is 34 at night and it can keep Ice cream frozen. It recovers quickly when opened.  It was left unused for years.

1. Have you checked to make sure that your rv is level? Or nearly level..

2.This no-start happens to us when I switch the fridge from gas directly to elect. mode  without stopping at off first.      

  On 10/31/2019 at 5:28 AM, Kahoona said:

Interestingly I should mention that that fridge used to work terribly. Never got below 38 and was often in the upper 40's in the day. Opening the door caused a rise of 2-3 degrees which took hours to come back. Since I have run it for 2 weeks straight it has gradually improves to where it is 34 at night and it can keep Ice cream frozen. It recovers quickly when opened.  It was left unused for years.

Is the operation you are describing here operating with power directly to the 120V heaters? If so that would mean that it is in a constant cool mode since there is no control function. In a healthy cooling unit the continuous operation mode will usually freeze everything if left overnight. If yours can work in constant cool mode and never freeze the lower part of the refrigerator, I have to suspect that the cooling system has issues, but do not see how that could prevent the automatic shift to 120V. Most RV refrigerators do cool better when using propane because it is typically a significantly better heat source. How old is the subject refrigerator? It is sounding to me like you may have more than one problem.

  On 10/31/2019 at 8:58 PM, Kirk W said:

Is the operation you are describing here operating with power directly to the 120V heaters? Yes If so that would mean that it is in a constant cool mode since there is no control function. In a healthy cooling unit the continuous operation mode will usually freeze everything if left overnight. That is part of the reason I need to get it running the right way. I agree. If yours can work in constant cool mode and never freeze the lower part of the refrigerator, I have to suspect that the cooling system has issues, but do not see how that could prevent the automatic shift to 120V. Thanks, Agreed.That is what is making me crazy! Some say that letting these sit unused for long enough will cause either a sludge like formation or a chemical combination that might be reversed. Once it was put on direct AC  (on the sunny side of the RV) the overnight cooling improved by nearly a degree a day until it got down to 34f. It may improve more but it it makes it to 34 in a tropical temperature I would be happy if only it would function with the proper controls.  Most RV refrigerators do cool better when using propane because it is typically a significantly better heat source. How old is the subject refrigerator? The RV  a 2008 and it had 23,000mi on it. I knew that there would be problems from sitting too long when we got it  but the price was so attractive that I could spend a couple of months and a few thou on it and still do great. is It is sounding to me like you may have more than one problem. Yes, the fridge  had many problems, mainly with poor install and rubber parts mostly fixed now but the AC not passing through is the one I need to focus on now. It is a RM1350, often considered the worst functioning fridge ever. Since I can get 34f I'm  happy.

 I am absolutely baffled. Everything tests correctly and the heaters are delivering heat to the boilers when connected directly. Somewhere there is one connection or little bit of hardware that is failing in an unusual way and I can't find it. Today I have other things I have to do but I will talk to Dinosaur and Dometic as has been suggested. I will also read the service manual again very carefully looking for hints. Anything that anybody can suggest might be the thing I need to hear so all advice is appreciated greatly.

  On 10/31/2019 at 7:38 AM, Don SC said:

1. Have you checked to make sure that your rv is level? Or nearly level..

2.This no-start happens to us when I switch the fridge from gas directly to elect. mode  without stopping at off first.      

Yes it is level and works on gas.

Interesting. 1he 1350 has soft touch buttons and goes straight to auto when turned on. In the end I may wind up installing a switch to choose elect or gas like yours.