How do I solve c2557 error ?

Replace Drum Unit and Developing Unit.
if still, then look for c2557 troubleshooting.
i have already explained on this portal

Sounds like a sensor is broken. Whatever caused the initial errors was not fixed and continued use has permanently broken the product.

replace k iu and developer /open close the front door but it will be back until you replace the parts

Abnormally low toner detected TCR sensor.
Problem with the developer, toner sensor, or if a PM was done and the counters were not cleared property. Open and close front door to reset. If error returns, check developer unit.

Hi,
C2557: Abnormally low toner density detected black TCR sensor.
Detailed Error code explained below.
Possiable solutions.
* Open and close the front toner door.
* Restart the machine by turning off the LCD screen power switch, then by the main body switch located behind the access panel above tray 1 indicator light.
* Call Konica to get a tech out.
C2557 Abnormally low toner
density detected black
TCR sensor
• When sampling data is determined in TC
ratio calculation control, TCR sensor output
is higher than a predetermined value for a
predetermined number of times in a row
even though there is toner in the sub hopper.

Replace the image unit. open the right side cover pull out he old image unit and install the new one

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

Error code c2557 means "Auto Toner Density Control sensor abnormality" (ATDC)

This code happens if you replace drum without replacing developer. Both must be replaced at same time.

Reset it, start it with the right door open, go to service mode, clear the counters for drum and developer and go to functions menu. Close the right door and start immediately the F8 function. It should work.

hi,

open and close front door cover to reset error.

If it persists you have to execute (TCR Toner SUPPLY)

Tell me if you need to execute it.

Bye.