All ActivityMost RecentMost LikesSolutionsDometic AC/HP (1500BTU's) ambient temp sensorsMonaco Windsor 2001...Dometic Model # 651816CXX1C0 (1500BTU's) E4 Code is: open circuit or Outdoor ambient Temp. sensor.... I have replaced a few of these temp. sensors in the last few years.. Is anyone having the same issue? I have 2 units and they go bad on both units... Is there a cause anyone knows about or do they just go bad in time?? Thanks in advance, Tom BTW I'm getting pretty good at replacing them :-)Re: Dometic Comfort Control 2 model#3314080.xxx(E4 code)We did a reset when we got to Arizona and it is now working just fine....Thanks again for the great reply's and info it was truly a great help...Tom P.Re: Dometic Comfort Control 2 model#3314080.xxx(E4 code)Update.... I will be heading to Arizona Monday from near Hershey Pa. and will fix the AC/HP unit when I get to AZ and will update then... Getting ready to go to Az has been taking most of my time.... Just didn't want you guys to think I forgot about the fix... Thanks Again, Tom P.Re: Dometic Comfort Control 2 model#3314080.xxx(E4 code)Didn't get to check the issue yet got busy again....but will update when I do get at it...Thanks again for the great tip/info....Tom P.Re: Dometic Comfort Control 2 model#3314080.xxx(E4 code)I got busy today but will check it tomorrow....I will update what I find....Tom P.Re: Dometic Comfort Control 2 model#3314080.xxx(E4 code)Thanks Guys...And yes I did replace the ambient temp sensor a year ago.... I will check both... Tom P.Re: Dometic Comfort Control 2 model#3314080.xxx(E4 code)I can't seem to find a diagram for my AC/Heat Pump Dometic #651816CXX1C0 15K? On line.....Re: Dometic Comfort Control 2 model#3314080.xxx(E4 code)thanks for that...the controller box is on the roof unit?right....not sure what the freeze sensor looks like.... Sorry for not knowing the parts....I have already replaced the ambient temp sensor about a year ago and it was on the roof unit. I will go on line and try to find the diagram for the unit.... Thanks again....Dometic Comfort Control 2 model#3314080.xxx(E4 code)Dometic Comfort Control 2 model#3314080.xxx(without dehumidify) has a E4 code... Breaker is good..It was working earlier today fine... Can anyone tell me what to check or what the issue normally is??? Thanks in advance Tom P.Re: Dometic Comfort Control 2 Thermostat issueThanks all for the great comments/suggestions ! It was the the outside Temp sensor!!!! I switched the back AC/HP sensor with the front and the front worked fine....So the front sensor was bad and I have one ordered and on the way...... Again this forum has saved me a ton of cash/time being able to get the tech info to help trouble shoot an issue....Then do the work to find the issue and replace the bad part etc etc....Thanks again,Tom