02/20006-35DocuPrint N2125 GP 3.6 , GP 3.7General Procedures / InformationInitial Issue• Warm-up failure - SOS signal intervals are longer than the READY reference value duringthree consecutive samplings of the SOS. The actual laser power does not equal the valueset in NVRAM.• Laser speed too low (Down Failure) - SOS signal intervals are longer than the set DownFailure interval after completion of warm-up. The set Down Failure is a time interval corre-sponding to 90% of the rated Laser Motor speed of rotation.• Laser speed too high (Overrun Failure) - SOS signal intervals are shorter than the setOverrun Failure interval after completion of warm-up. The set Overrun Failure is a timeinterval corresponding to 102% of the rated Laser Motor speed of rotation.GP 3.7 Fuser ControlFuser Temperature ControlThe Thermistor monitors the temperature on the surface of the Heat Roll and compares thattemperature with the rated temperature that was set in NVRAM. The Print Engine Controllerswitches the Heat Rod on or off depending on how the actual temperature differs from the ratedtemperature.Fuser Temperature AdjustmentYou can adjust the rated Fuser temperature by changing the NVRAM Value. You can adjust thesetting in 16 increments, with each increment approximately 4°C.The printer switches on the Heat Rod when the Fuser temperature lowers below the currentcontrol temperature (approximately 178°C for the standard control temperature). The printerswitches off the Heat Rod when the Fuser temperature rises above the current control temper-ature (approximately 180°C for the standard control temperature).Fuser Warm-upPower to the Heat Rod is applied at the start of printer warm-up. Warm-up is complete whenthe Heat Roll reaches the current control Temperature. If the Fuser Temperature is below100°C at start of warm-up, then warm-up finishes when the Fuser temperature reaches"standby temperature".Fuser Trouble (U4 Error Code)There are five major causes of a U4 error.• Warm-up failure - Fuser warm-up does not complete within specified seconds after start-ing.• Low Trouble temperature - The Fuser temperature drops to the Low Trouble temperature(approximately current control temperature, minus approximately 25°C• High Trouble temperature -The Fuser temperature rises to the High Trouble temperature(approximately current control temperature, plus approximately 35°C• The Thermistor circuit opened.• STS failure -The Heat Rod remains on for at least ten seconds after warm-up has com-pleted.AC Power Shutoff to the FuserThere are eight reasons that the printer shuts off AC power to the Fuser.• Fuser Failure (U4)• Paper jam• Open Front Cover Assembly• Laser failure (U2)• CPU or NVRAM problem (U6)• Main Motor Assembly problem (U1)• Fan problem (U5)manuals4you.commanuals4you.com
