Ricoh SP C811DN error sc549

check the ferrite roller HP sensor.

Turn the machine off. Open the access door and remove the cyan photoconductor unit. Check the contact pins are straight and undamaged. Gently reinsert the unit. Turn the power back on. If the machine still does not recognise the pcu is inserted it is probably damaged and needs replacing. How many copies/prints has your machine done?

This is a ITB contact motor error.
Check/clean/replace contact sensor.
Replace transfer belt contact motor.
Check harness and connectors to motor and sensor.
Check for mechanical binds.

fuser encoder error

-replace Encoder Ferrite core switch - B2234240

-replace Photo interuppter - Horizontal 7mm AW020190

Perhaps, it is a faulty PCU. Try by shutting off power and using another but wait a few minutes before turning it on again.

https://www.youtube.com/watch?v=vSjDCb7iN-E

Here is a way to reset but make sure you follow the instructions correctly.
turn off machine
press online and escape buttons together whilst turning on machine,
when display comes up wait till three options are listed, use arrow button down to select engine, use arrow right to select mode(5.mode) and ok, left arrow to 5.810 SC RESET. OK. PRESS OK AGAIN AND THEN EXECUTE AT BOTTOM OF SCREEN.
Turn off printer and wait ten secs then turn back on.
If only temp error this should reset and start up again, Good luck

Changing the fusing unit might solve the problem

It's the fuser. You can try turning it off, wait 30 seconds, and turn it back on again.

If the problem continues, call a technician in to get the thermistor replaced.

It's a common error.

No.
Type
Details (Symptom, Possible Cause, Troubleshooting Procedures)
553
A
Heating roller overheat (software error)
The detected heating roller temperature stays at 230°C or more for 1 second.
• Defective PSU
• Defective lOB
• Defective EGB
Related SC code: SC 543
1. Replace the PSU.
2. Replace the lOB.
3. Replace the EGB.
This is the simptoms of the service manual , you should check that your power output is stable and double check if there is not anything like paper stuck some were in the fuzing unit wich could also cause the fuzer to over heat