
Solutions for the Prompt "Call service. C7900" on Kyocera FS-1800 Printer
Background
Customers have reported that the Kyocera FS-1800 printer displays the prompt “Call service. C7900”(Figure 1). This indicates that there is a faulty connection between the printer and the cartridge drum unit. The main reasons for this are that the drum unit screws are installed incorrectly and/or there is an issue with the chip inside the drum unit.
(Printer models include Kyocera FS-1800/1801/2200/2201/2010/2011. )

Figure 1
Zhono Solution
Step 1: Remove the drum unit and check to see if the drum unit screws were installed correctly. If not, adjust them as necessary. Then, install the drum unit back into the printer. If the prompt “Call service. C7900” still displays, please follow the next step.
Step 2: Replace the drum chip. For more details about replacing the drum chip for Kyocera FS-1800/1801/2200/2201/2010/2011, please refer to the video below.
Note:
Avoid damaging the OPC drum during the replacement process. If the OPC drum is scratched, printer quality will be affected.
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