• Code: 542
• Description: Fusing temperature warm-up error
  Just before reaching warm-up temperature, the fusing temperature did not rise above 80C within 17.5 sec. after the power relay switched on. Note: • The machine starts to test the temperature 2 sec. after the machine powers on if the machine temperature is above 45oC. • If the machine temperature is below 45C, the temperature is not sampled until the machine temperature reaches 45C.
• Causes: • Thermistor defective • Fusing lamp open • Fusing thermostat open • Power supply board Defective • Defective connection of the fusing unit

• Code: 543
• Description: Fusing overheat error - software
  The fusing temperature was detected higher than 24oC for longer than 200 ms while the main motor was on or within 60 sec. after the main motor switched off. -or- The fusing temperature was detected higher than 235C for longer than 200 ms at any other time.
• Causes: • Fusing thermistor defective • Power supply board defective

• Code: 545
• Description: Fusing lamp remains on
  The fusing lamp remained on longer than 12 sec. after the fusing unit reached optimum temperature and the main motor switched off.
• Causes: • Fusing thermistor defective • Power supply board defective • Defective connection of the fusing unit

• Code: 546
• Description: Unstable fusing temperature
  During standby, the fusing temperature went below 60 °C twice or went above 60 °C three times within 500 ms. A 60C increase in fusing temperature was detected at five 1-sec. intervals within 60 to 90 sec. before reaching fusing temperature.
• Causes: • Fusing thermistor defective • Power supply board defective • Defective connection of the fusing unit

• Code: 547
• Description: Zero cross signal error
  Zero cross signals of wavelength 50-60 Hz were not detected within 5 sec after the fusing relay switched on .-or- Zero cross interrupts did not issue at the prescribed 1 sec. intervals.
• Causes: • Power supply board defective • Defective mains power supply condition

• Code: 559
• Description: Fusing unit jam
  Three consecutive paper lag jams (paper failed to arrive) were detected in the fusing unit. -or- During printing of the 1st side during duplexing, the paper did not arrive at the duplex entrance sensor three times. Note: SP1913 determines whether SC559 is issued. The default is off. SC559 is not issued after three consecutive jams in the paper unit. If SP1913 is set to on, turning the machine power off/on does not reset the jam counter.
• Causes: • Fusing unit installed incorrectly • Fusing unit defective

• Code: 590
• Description: Fan motor error
  The machine detected an error in the fusing unit fan or the PSU fan. Either or both fan motors started to rotate within 10 sec. after power on.
• Causes: • Fan motor disconnected, defective • Fan motor harness loose, broken, defective

• Code: 610
• Description: Communication error - duplex unit
  The engine board could not communicate with the duplex unit. (The duplex unit did not respond within 1 sec. to a status request.) Note: This SC is logged, not displayed.
• Causes: • Defective connection between engine board and duplex unit • Engine board defective • Duplex control board defective