Kyocera ECOSYS M4125idn

1. The size of paper set in the cassette is misdetected or not displayed

Object: Main unit, Paper feeder

Step	Check description	Assumed cause	Measures
1	Checking the paper length switch and fan-shape arm	The paper length switch or fan-shape arm does not operate properly	Reattach the paper length switch or fan- shape arm
2	Checking the connection	The connector is not connected properly, or the wire is faulty.	Clean the terminal of the following wire connectors and reconnect the connectors. If there is no continuity, replace the wire. Paper length switch - Engine PWB Paper width switch - Engine PWB
3	Replacing the paper length switch	The paper length switch is faulty	Replace the paper length switch
4	Replacing the paper width switch	The paper width switch is faulty	Replace the paper width switch
5	Replacing the Engine PWB	The Engine PWB is faulty.	Replace the Engine PWB.

2. The main unit malfunctions even if turning on the power switch

Step	Check description	Assumed cause	Measures
1	Measuring the input voltage	The power cord has no continuity.	Plug the power cord into another wall outlet.
2	Checking the power cord	The power plug of the power cord is faulty.	If the power plug is deformed or faulty, replace the power cord.
3	Checking the power cord	The power cord is faulty.	If there is no continuity of the power cord, replace the power cord.
4	Checking the power switch	The power switch is faulty.	Check the continuity between the contacts of the power switch. Replace the power switch if there is no continuity.
5	Checking the low voltage PWB	The connector is not connected properly. The wire or the PWB is faulty.	Clean the terminal of the connectors on the low voltage PWB, then reconnect the wire connector. If the wire is faulty, repair or replace it. If not repaired, replace the low voltage PWB.
6	Checking the main PWB	The connector or FFC terminal is not connected properly. Or, the wire, FFC, PWB is faulty.	Clean the terminal of the connectors on the main PWB, reconnect the connector of the wire, and reconnect the FFC terminal. If the wire or the FFC is faulty, repair or replace them. If not resolved, replace the main PWB
7	Checking the Engine PWB	The connector or FFC terminal is not connected properly. Or, the wire, FFC, PWB is faulty	Clean the terminal of the connectors on the Engine PWB, reconnect the connector of the wire, and reconnect the FFC terminal. If the wire or the FFC is faulty, repair or replace it. If not resolved, replace the Engine PWB.