Hi there and welcome!
From what I read that error has to do with temp probes (thermometers) in your smoker. This is not a common problem.
It usually happens in cold weather environments and people simply heat up the inside of the smoker with a hair dryer OR they hold a lighter to the temp probe to heat it up.
If you are located in the USA then it is not a cold weather problem this time of the year.
If not cold weather related then your temp probe(s) or any of the electronics along the way from the bottom circuit board to the top controller could have an issue.
At this point I can suggest a fool proof option that cost a little money to get a PID controller (about $150), but costs less than a new smoker, and will mean cutting 4 wire ends and then splicing with 2 wire nuts to make 2 new wires.
Doing the simple rewire and using a PID controller will turn this smoker into something 25x better than it was or anything
Masterbuilt makes brand new. It will basically be better than anything under $1,000.
Also you will be very close to keeping this thing running in the future through anything short of it being hit by a car :D
A number of us guys have done this with our MES smokers and I believe every single one of us would never go back. Hell I think every single one of us wonders why we didn't do it sooner hahaha.
You can still be up and going and better than ever. Ask all the questions you have and we can get you there if you are interested :D
Here's a detailed write up on the simple rewire of an MES smoker to use a PID controller:
Lately I've seen a number of posts about guys wanting to rewire their MES. I had wanted to post a quick and simple guide for those out there that are curious or those that simply need to rewire but need a little assistance. Well here goes. Disclaimer: When messing with electrical equipment...
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