Kyocera P6021cdn - Znaczenie i naprawa błędu 7403:0015121

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Code: 7403
Description:
Developing unit M noninstalling error
No density detection signal is output from toner sensor M in developing unit M.
Causes:
Defective connector cable or poor contact in the connector. Defective toner sensor M. Defective engine PWB.
Remedy:
Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Developing unit M and Drum relay PWB (YC7) Drum relay PWB (YC1) and engine PWB (YC34)
Defective toner sensor M. Replace the developing unit M.
Defective engine PWB. Replace the engine PWB and check for correct operation.