Analysis of the possible causes of this failure:
1.) Determine whether the purchased thermal paper is aspecial thermal machine printing paper. Judgment method: scratch the paper with a fingernail or a sharp object, and black marks will appear, as if written with a pencil and slipped on the white paper , if there are traces, it means that the thermal paper can be purchased, otherwise try to change the thermal paper.
2.) The pressure of the printer roller is not necessarily normal when the thermal paper enters and exits normally. Take it apart and check whether the roller is pressed against the thermal paper surface when the printer is working. Otherwise, the print head cannot touch the thermal paper, and it will not help no matter how hot it is.
3.) If the thermal printer is in the form of ribbon, it is necessary to check whether the ribbon can be transferred normally when the printer is working. If not, try to replace it with a new one.
4.) If the possibility of the above three reasons is ruled out, it is very likely that the print head of the thermal printer is broken and cannot work and print. It is recommended to replace it with a new one.