OKI MC363

Troubleshooting. Abnormal MFP operation after powered on. No operation

Check item	Checking method	Action
Checking connections
Connection between the printer and AC power supplied	Check the connection between the printer and AC power supplied.	Connect the AC cable properly.
Cable assembly connecting low-voltage power supply unit to CU/PU board	Make sure the low-voltage power supply unit is connected to the POWER connector and SP connector on the CU/PU board properly. Check whether the cable connector is half-connected or tilted.	Connect the cable properly.
	Check whether there is any fault in the cable assembly, e.g., missing wires.	Replace the cable with a good cable.
Connection between CU/PU board and SU board	Make sure the 16-pin FFC is connected to the OPE_OPM connector on the CU/PU board properly. Make sure the 16-pin FFC is connected to the OPE1 connector on the SU board properly. Check whether the cable connector is half-connected or tilted.	Connect the FFC cable properly.
	Check for broken wires using a tester. Check visually whether the sheath peels.	Replace the FFC cable with a good cable.
Connection between SU board and OPM board	Make sure the 16-pin FFC is connected to the OPE2 connector on the SU board properly. Make sure the 16-pin FFC is connected to the CN1 connector on the OPM board properly. Check whether the cable connector is half-connected or tilted.	Connect the FFC cable properly.
	Check for broken wires using a tester. Check visually whether the sheath peels.	Replace the cable with a good cable.
Confirmation of the power switch LED
Power Switch LED	Confirm whether the LED is off. If the LED blinks rapidly, the number of blinking times in a cycle shows an error. The timing of blinking rapidly is shown in the below figure	Replace either of the low-voltage power supply unit, the CU/PU board, Power SW-board, the cables connected to the low-voltage power supply unit and CU/PU board or the cables connected to the CU/PU board and Power SW-board. In case of 2, 4, 8 or 10 times of LED blinking rapidly: Replace either of the low-voltage power supply unit, the CU/ PU board, the cables connected to the lowvoltage power supply unit and the CU/PU board. In case of 3, 6 or 9 times of LED blinking rapidly: Replace the CU/PU board.
Checking power supplies
AC power supplied to printer	Check the supplied voltage of the AC power supplied.	To supplies the AC power
AC power supplied to CU/PU board	Check the supplied voltage of the connector on the CU/PU board. A)POWER connector 1, 2, 3pin: 5V 7, 8, 9pin: 24V 4, 5, 6pin: 0V B)SP connector 1pin: 3.3V 2pin: 0V	Replace the low-voltage power supply. Replace the POWER cable or SP cable.
AC power supplied to SU board	Check the supplied voltage of the POWER connector on the SU board. 1pin: 3.3V 3, 4pin: 5V 7, 8pin: 24V 2, 5, 6, 9, 10pin: 0V	Replace the CU/PU board or cable.