I came in possession of a B1 SE Plus with E1 error with hotend not heating. After testing the resistance I ordered the heater cartridge which came with the thermistor. It should be pointed out that shipping was more than the part and took forever to get here. But I knew that going in. I would have bought more parts but wanted to make sure the printer was worth putting the time and effort into it. Replaced the cartridge and the printer is now working. Simple plug and play. I also had to replace the Y endstop. An item I must point out that was not available from BIQU. Since the printer works I will now look into spending more for items like dual z parts and a better build plate. I am quite impressed with the prints so far. Winner in my book. Thanks