NORCOLD 1210 5 amp fuse blows when opening either door

I've looked through the forum trying to find a similar problem. If posted I did not find it.

Our 2014 Landmark Rushmore has been relatively problem-free until yesterday. Opened the refer door and there was no light and noticed the unit was off. Downloaded the service manual and traced to a blown 5 amp fuse on the control board in the outside part of the refer unit. Replaced the fuse and the unit started and seemed to be working fine. That is until I opened a door.

I disconnected the thermistor/light harness to isolate that, and still blows the fuse. It does not make any difference which door of the refer is opened. Either door, when opened, will blow the fuse. Each time the fuse is replaced and the doors are kept shut the unit seems to work fine. I've checked and it is not throwing any codes.

I disassembled the front of the refer looking for any pinched wires between control module on the front and further in. I did not remove the light switches on the door as I could not figure out how to pop them down. Something seems to be pinched downstream of the light switch causing the short when the switch is closed and subsequent fuse to blow. However, it perhaps could be something else.

I'm pretty much a newbie with this has stumped me and need some help. We are full-timers and need to get this working.

Thanks for any assistance!

Assuming you can't follow the wire from power board to the lamp, and if you can figure out which wiring diagram applies to your S/N refrigerator, you might locate the connector that provides the 12V DC to the lamp and try to remove just that 1 pin to see if the problem goes away. If it does, perhaps you can cut the original wire near the connector and run a new wire to the lamp.

While you work out the real problem get some good tape and tape the switch in the door closed position.

You’ll have to get stuff in the dark but at least the frig will stay running.

If you can’t find the problem you could probably rig up a separate switch.

Thanks, danemayer, for the suggestion. My problem is that I can't figure out how to gain access to the wires between the switch (how to remove the switch) and where they exit near the lamp/thermistor harness. Does the whole refer have to be pulled and access is from the back of the unit?

Thanks, Garypowell, for the handy short-term fix. I've been so focused on getting the root cause solved, I didn't think about a short-term solution. Great idea!

Tian:
I studied the wiring diagram for the Norcold 1210 I found in a manual online:
https://www.thetford.com/wp-content...d-Ultraline-1210-Owners-Manual-AC-Current.pdf

This isn't your simple "1 switch contact makes ground to light the attached light" type of refrigerator light circuit I am familiar with. In this one the door switch has 3 sets of contacts mainly having to do with a door gasket heater system. The light bulb and thermistor are together in another place remote from the switch. I have a hunch that your fuse blowing has something to do with the door heating circuitry, since any heating involves a fair amount of current flow.

This problem probably needs a professional with years of on-the-job experience with RV refrigerators to figure it out. I looked at your profile, saw that you are in the Dallas area, and did a websearch for RV appliance repair in your area. I found one mobile guy that SPECIFICALLY mentions RV Refrigerators in his list of qualifications. The website was professional and impressive, too. If it were me, I would turn this one over to the experienced professionals. Maybe he has seen it before, maybe he has some networked contacts to a "Norcold Guru". Here is the website listing: http://ryansrvrepair.com/ .

Good Luck!!!

A hearty thank you to y'all who responded and quick update:

Through extremely fortuitous circumstances as we are traveling and currently in Idaho, we were able to get our trailer into Smith RV in Idaho Falls, ID today. With my troubleshooting information and the information supplied by wdk450 (below), the tech was able to quickly determine that the short was located in a section of the unit that is totally sealed. Diagnosis: full replacement of the reefer!

Thankfully, when we purchased the trailer last fall we opted for an extended warranty. This expensive full replacement will only cost us the $100 deductible! The replacement reefer is on the loading dock this afternoon with an estimated delivery date of Monday and in install date of Tuesday. We should be back on the road on Wednesday next week!

In addition, thanks to Garypowell's suggestion below, we actually have an operational reefer until the new one is installed. Okay, so the illumination inside the reefer is not all that great; but hey, our grub is cold! 😄

We even have a place to stay with free water and electricity for the duration of the repair at Smith RV. Lot's of blessings today!

Thanks again, y'all. There really are great and wonderful things that happen in this world! 🤠