My Konica Minolta bizhub 211 says: "machine in trouble call service C0501" what can I do?

It is a generic warm up failure. You need the service call.

Code: C3451 · Description: Fusing Warm-Up Failure (Main) - The Fusing Roller Thermistor does not detect the required temperature

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Konica-Minolta bizhub 195 - Error Code - PrintCopy .info

https://printcopy.info > model=bizhub 195 > code=C3451
Code: C3451; Description: Warming-up failure - The thermistor/1 (TH1) detected that the temperature of the surface of the fusing roller did not reach the ...

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  Konica-Minolta bizhub 350 - C3451 - PrintCopy .info

  https://printcopy.info > model=bizhub 350 > code=C3451
  Konica-Minolta bizhub 350 · Code: C3451 · Description: Fusing Warm-Up Failure (Main) - The Fusing Roller Thermistor does not detect the required temperature ...

https://www.manualslib.com/manual/837626/Konica-Minolta-Bizhub-162.html?page=174

Error code C0500 and C0501 means Fixing unit's temperature abnormality.

How to reset these codes?

To reset Error codes C0500 and C0501, perform the following steps.

1-Turn the machine "OFF".
2-Press the "STOP" button on the basic panel.
3-Keep the button pressed and turn the machine "ON".
4-Do not release the button, until the machine warm up.
5-After few seconds Error code will remove and machine will reset.Basic menu will show no error on LCD screen.This means error code has been removed and photocopier machine is ready to use.

http://servicekonicaminolta.blogspot.com/2012/03/error-code-c0500-and-c0501.html

what wrong with the machine before resetting it

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/normanj_7893313f0751935f

machin trouble service call (c3451)

Maintenance call? from your question it is not clear what is the error code.Please see if there is any code appearing besides maintenance call.Note the error code and tell me again so that i can help you.If it is C0500 or C0501 then press the stop button on the panel and restart the machine do not release the button until the code removes.

how can i reset the password for my konica minolta bizhub 211 to remove the maintainance call 2 display?

turn off the machine, press the stop button, turn the machine ON, and keep the "STOP" button pressed, C0501 error code will reset in few moments...............

COF32 means the ATDC sensor has detected some unusually high or low readings.
The ATDC sensor measure the toner lever inside the developer unit.
Try swithcing on/off, open/close the front door to clear the code.
If this doesn't work, you'll need an engineer to reset the ATDC level.

Good luck

Tam

C0501 it is a trouble related with the Fusing Unit. Try to power it up with the STOP button pressed. If not, you may need to change your fusing unit.