Description: Toner sensor problem • The sensor output voltage is outside the range of 0.5 to 4.5 V during toner control. • The toner sensor control voltage cannot be set within the setting range when maintenance item U130 is run.
Causes: Defective toner sensor. Poor contact of the toner sensor connector terminals. Developer problem.
Remedy: Replace the toner sensor. Reinsert the connector. Also check for continuity within the connector cable. If none, repair or replace the cable. Replace the developer.
Code: C730
Description: Broken external temperature thermistor wire • The input voltage is above 4.5 V.
Causes: Poor contact of the humidity sensor PCB connector terminals. Defective external temperature thermistor.
Remedy: Reinsert the connector. Also check for continuity within the connector cable. If none, repair or replace the cable. Replace the humidity sensor PCB.
Code: C731
Description: Short-circuited external temperature thermistor • The input voltage is below 0.5 V.
Causes: Poor contact of the humidity sensor PCB connector terminals. Defective external temperature thermistor.
Remedy: Reinsert the connector. Also check for continuity within the connector cable. If none, repair or replace the cable. Replace the humidity sensor PCB.
Code: C740
Description: Image formation unit connector insertion problem • Absence of the image formation unit is detected continuously for 1500 ms while there is no error on the copier.
Causes: Image formation unit connector inserted incorrectly. Defective image formation unit connector.
Remedy: Reinsert the image formation unit connector if necessary. Replace the image formation unit.