Heating error when heating

I've been using this CR-X printer for years. Recently it gave me a heating error. So I replaced the hot-end heater. Then the thermal-couple. The I replaced the motherboard. Still getting the error.

The board on the arm had a bad soldar spot I think I fixed but maybe not. It was where the hot-end connects, so maybe i didn't fix it. Where can I get that board? I sent a request to Creality but didn't hear back, yet.

What board is it? There should be a marking on the board that identifies it and a quick search on ebay or amazon would likely give you a source and price.

One of the nice things about 3D printing is that most of the parts are used in many different devices and readily available.