Sharp MX-4112N Fuser Trouble

[Eirik]

Hi

I have a Sharp MX-4112N in my workshop that constantly comes up with H2-01 error code (thermistor trouble).
I have changed both thermistors and all the thermostats, still did not fix it. Any thoughts?

[Eirik]

Update:
The fuser does not heat up after themachine has been turned on for more than an hour.
Still it does not work to upgrade firmware or use fuser trouble cancellation simulation

[Akitu]

4111 Fuser.jpg

As you can see in the image from page 26 of the service manual there are 3 thermostats. You said you changed both of them so you obviously missed one. Try changing the correct one and your problem should be resolved.

[faxman28]

H2-01 is open thermistor on lower roller(pressure roller).

Thermistor is bad, put you said you replaced, check resistance of thermistor , with meter, usually in the 30 to 70k ohm range, compare with known good thermistor
PCU board is bad, no voltage going to thermistor . Check voltages at connector on PCU board.
Something wrong with fuser connector on fuser and/or main body.

Wrong fuser. fuser for mx4110 series and mx5110(fuser looks the same and most parts are the same) are different,put wrong fuser in will get error. Sharp usually changes the pins for thermistors on fuser connector , so the wrong fuser will just code out (been there and done that).

[Eirik]

Yes i changed 3 thermostats and both thermistors, didnt miss any of those. But i do think i have an MX-510FU
in the 4112N so the problem might fix itself if i order a new MX-410FU. I shall also check the thermistors with a multimeter.
Thanks