I found out that the RJ11 plugs on regular temperature sensors were not crimped well by my manufacturer.
I have been re-crimping them before shipping them, but I might have missed some in the first orders.
The contacts should lay about 1 mm below the plastic, not at the same level.
Please refer to the photo below. Good crimp on the left, bad crimp on the right.
The sensors with a bad crimp can be unreliable and it increases the wear on the socket.
With a network crimp tool like this, it is easily fixed, just by inserting the plug and pinching it. The crimp tools for RJ45 network cables usually also have an insert for RJ12 plugs (6pins).
Sorry, me post earlier was merely speculation on a problem easily solved by @Elco. I am currently running my brew fridge with no problems and looking forward to updating to the latest release when this fermentation is done.
If you do have one of the bad ones. Don’t freak out. Just out the cable in your pocket and drive to your favorite home improvement store and go to the electrical tools section. You don’t have to buy the tool. Just pull out the cable you brought with you. Under it into the crimper and squeeze the handle. Then casually walk back out.