I’ve had this printer for a little bit more than a year, and of course right after warranty I run into an issue. I’ve replaced several parts, including the hot end, the small board that connects to it, and the large print head cable. I continue to run into error code TE2509. When trouble shooting I noticed this solder and maybe I’m going too in fine detail. I’m not too knowledgable about this kind of thing but the second pin from the bottom seems to not have solder or an “empty” connection. Does this mean anything?
I have had a raft of these faults and still get them about once a month. In my case the front small board connector to the thermistor broke. I soldered new pins in from an old resistor and the printer worked but with a temperature offset due to the differing metals now installed in the circuit. Creality sent a new board and all is good for a month at a time. When the print fails now due to temperature not being maintained I wiggle both connectors (hot end and thermistor) on that small board and the printer is good for another month. Dielectric grease had no measurable effect. Where is that connector that you have such a clear picture of and how did you get to it. Do you have a picture of the back of that board and that pin? Usually these boards are “wave” soldered and it looks like that connection is defective. If there is not solder on the back of the pin board connection, reflowing the board will do not good. If time permits I will take mine apart and get pictures of mine to post. My bets are that the lack of solder in that pin is causing a random poor or variable connection as the printer heats up and the print fails. If you have a temperature controlled soldering station it can be easily fixed with a bit of flux and standard solder. From the back of the board is usually best. From the back of the board you will be able to see if there are any other pins that are not correctly soldered too.
