Konica Minolta Biz hub c450 code c-2558

[cartridgeprinter]

I have a customer with a Biz Hub c450. It have several error codes on it. After replacing all the imaging units and cleared all the codes except for c-2558.

I thought it had somethign to do with the Black imaging unit.

What is the error code and what do I need to do?

Thanks

[CMB]

C2558 Abnormally high toner density
detected Black TCR Sensor
• T/C 12 % or more is detected ten consecutive
times in the Developing Unit as validated through

the toner replenishing amount determination control.

C2558: Abnormally high toner density detected Black TCR Sensor

Relevant Electrical Parts
Imaging Unit /K
TCR Sensor/K (PWB-N4)
Control Board (PWB-MC)
MFP Control Board (PWB-MFPC)
Step Action
WIRING DIAGRAM
Control Signal
Location
(Electrical
Component)
1
Correct the TCR connection on the underside of
the Imaging Unit if faulty.
— —
2
Clean or correct each contact of the Imaging Unit
if faulty.