Canon LBP 2460 Service Manual - Page 61

CHAPTER 2 3) Reports the fixing unit failure to the video controller. 4. Fixing roller heater start sequence The sequence of operations from the power ON to the standby is as follows: 1) The CPU outputs the fixing sub heater drive signal and then the fixing main heater drive signal to prevent the surge current from increasing after the power is turned ON. 2) If the upper fixing roller temperature reaches 169 to 177°C (180°C for temperature adjustment in the morning), the CPU outputs the READY signal (/RDY) to the video controller. If this temperature is not reached within 180 seconds after the fixing roller heater turns on, the CPU assumes that a fixing unit failure has occurred. 3) After the /RDY signal is output, the CPU keeps the upper fixing roller temperature at 169 to 177°C until the PRINT signal (/PRNT) is sent from the video controller. Upper fixing roller temperature (°C) Abnormally high temperature-detection temperature 230 Normal print temperature 180 177 Standby 169 temperature 150 Abnormally low temperature-detection temperature Power ON /RDY signal ON /PRNT signal Last rotation ON start Figure 2-2-10 Time (sec) 2 - 15