In the maintenance mode, adjust the fixing temperature. If it does not work, replace the fusing assembly.
Canon has the function of preheating, which is to preheat in advance for better work. First, open the top cover of Canon copier. Then put the copy materials on the copy glass of Canon copier. After putting down the copy cover of Canon copier, click the circular icon on the operation panel of Canon copier. Then on the operation panel of Canon copier, press the left and right arrows to adjust the fixing temperature. Finally, every time you press the arrow, the fixing temperature will be displayed on the operation panel of Canon copier.