Description: Fuser unit error
HTEMP remains high for longer than 4 seconds since the heater lamp is on. The heater lamp continues to be turn on for longer than 60 seconds.
Causes: Blown-out thermistor. Blown-out heater lamp. Defective CPU U201 or comparator U205 on the engine board. Improper connector insertion. Defective power supply unit. Defective harness between fuser unit and power supply unit.
Code: 6020
Description: Abnormal high temperature error
CPU U201 detected that the HTEMP* signal (Abnormal temperature of more than approximately 220 °C) is low for more than 3 seconds
Causes: Defective CPU U201 or comparator U205 on the engine board. Defective engine board (KP-864). Defective thermistor. Defective photo coupler on the power supply unit for the heater lamp.
Code: 6400
Description: Zero cross signal error
The ZCROSS signal does not reach the engine board within 3 seconds after power on.
Causes: Defective power supply unit. Defective CPU U201 on the engine board.
Code: 7001
Description: Toner motor error
Toner motor is overloaded. TNMOC is detected by sampling every other 100 ms in 2 seconds since the main and toner motors are activated following the Replace toner Clean printer message after the Toner low TK-60 is detected.
Causes: Overcurrent in the toner motor circuitry due to an excessive torque, caused by hardened toner. Defective gate array U204 on the engine board. Improper connector insertion. Defective harness between developer and high voltage unit. Defective harness between high voltage unit and engine board.
Code: 7350
Description: Toner refreshing mode error
Causes: Defective high voltage unit.
Code: 8010
Description: Option bulk paper stacker HS-8E motor error
Motor error in the option bulk paper stacker HS-8E.
Causes: Defective harness (S02400) between engine board and option unit interface connector. Defective option bulk paper stacker HS-8E.