• Code: SC 220
• Description: Synch. detection signal error 1 220-001: Y 220-002: M 220-003: C 220-004: K0 220-005: K1 The front (for K&Y) or rear (for C&M) laser synchronizing detector board, which is used to determine the start timing of laser writing, does not send a signal while the polygon motor is operating normally and the LD is on.
• Causes: • Disconnection of the cable between front (K&Y) or rear (C&M) synchronizing detector board and the LD unit • Incorrect installation of front (K&Y) or rear (C&M) synchronizing detector board (the beam does not target the photo detector.) • Defective LD unit • Defective BCU • Defective +5VLD circuit
• Remedy: 1. Turn the main switch off and on. 2. Check the cable connection between front (for K&Y) or rear (for C&M) synchronizing detector board and the LD unit. 3. Check or reinstall the front (for K&Y) or rear (for C&M) synchronizing detector board. 4. Replace the front (for K&Y) or rear (for C&M) synchronizing detector board. 5. Replace the laser optics housing unit. 6. Replace the BCU. 7. Replace the PSU.

• Code: SC 221
• Description: Synch. detection signal error 2 221-001: Y 221-002: M 221-003: C 221-004: K Main scan length detection is not properly completed ten consecutive times. The front (for C&M) or rear (for K&Y) laser synchronizing detector boards are used for the main scan length detection, which automatically corrects the main-scan magnification.
• Causes: • Damaged or disconnected cable between front (C&M) or rear (K&Y) laser synchronizing detector board and the LD unit • Incorrect installation of front (C&M) or rear (K&Y) synchronizing detector board (the beam does not target the photo detector.) • Defective front (C&M) or rear (K&Y) synchronizing detector board • Defective LD unit
• Remedy: After doing any of the following, print ten jobs or more to see if the same SC code is displayed: 1. Turn the main switch off and on. 2. Check or replace the cable connecting front (for C&M) or rear (for K&Y) synchronizing detector board and the LD unit. 3. Check or reinstall the front (for C&M) or rear (for K&Y) synchronizing detector board. 4. Replace the front (for C&M) or rear (for K&Y) synchronizing detector board. 5. Replace the laser optics housing unit. 6. Replace the BCU. If a synch. detector board cannot be replaced, do the following as a temporary measure: • Disable main scan length detection (SP 2-919-001)

• Code: SC 230
• Description: FGATE error 230-001: Y 230-002: M 230-003: C 230-004: K The BCU generates the FGATE signal based on the registration sensor ON timing. Then, it sends the signal to the LD units. The LD units send a feedback signal to the BCU. When the LD units start emitting laser beams, the feedback signal changes from High to Low. The SC code is generated when the BCU receives no feedback signal (stays High) from the LD unit 1 second after paper reaches the position where the laser should start writing.
• Causes: • Poor connection between BCU and LD units • Defective BCU • Defective LD unit
• Remedy: 1. Turn the main switch off and on. 2. Check the cables between the LD units and the BCU. 3. Replace the laser optics housing unit. 4. Replace the BCU.

• Code: SC 231
• Description: FGATE timeout 231-001: Y 231-002: M 231-003: C 231-004: K When LD units emit laser beams to print a job, the feedback signal stays Low and becomes High after laser exposure for a page is completed. The SC code is detected in the following cases: • When the feedback signal stays Low 7 seconds after completing the laser exposure, or • When the feedback signal stays Low until the laser exposure timing for the next page in multi-page print mode.
• Causes: • Poor connection between BCU and LD units • Defective BCU • Defective LD unit
• Remedy: 1. Turn the main switch off and on. 2. Check the cables between the LD units and the BCU. 3. Replace the laser optics housing unit. 4. Replace the BCU.

• Code: SC 240
• Description: LD over 240-001: Y 240-002: M 240-003: C 240-004: K The power supply for the LD unit exceeds 67 mA.
• Causes: • LD worn out (current/light output characteristics have changed.) • LD broken (short circuit)
• Remedy: 1. Turn the main switch off and on. 2. Replace the laser optics housing unit.

• Code: SC 260
• Description: LD HP sensor not switched on (for K only) During homing, it takes more than five seconds to switch the HP sensor on (the sensor actuator does not cover the sensor).
• Causes: • Defective motor • Defective sensor • Mechanical problem when switching the actuator • Brown fuse (FU81) on the Power supply unit
• Remedy: 1. Turn the main switch off and on. 2. Check the sensor actuator position of the LD positioning motor. 3. Replace the LD positioning motor. 4. Replace the LD home position sensor. 5. Check and/or replace the PSU.

• Code: SC 261
• Description: LD HP sensor not switched off (for K only) After the laser beam pitch was changed, it takes more than five seconds for the HP sensor to switch off.
• Causes: • Defective motor • Defective sensor • Mechanical problem when switching the actuator • Brown fuse (FU81) on the Power supply unit
• Remedy: 1. Turn the main switch off and on. 2. Check the sensor actuator position of the LD positioning motor. 3. Replace the LD positioning motor. 4. Replace the LD home position sensor. 5. Check and/or replace the PSU.

• Code: SC 285
• Description: Line position adjustment (MUSIC) error Line position adjustment fails three consecutive times.
• Causes: • Pattern sampling error due to insufficient image density of patterns used for the adjustment • Inconsistency in the sampling line position adjustment pattern due to dust on the pattern, damage to the OPC drum, damage or toner dropped on the transfer belt, or a dirty or defective ID sensor
• Remedy: 1. Turn the main switch off and on. 2. Check and fix the problem that causes low image density. . 3. Clean or replace the transfer belt and/or the ID sensor. 4. Replace the PCU or clean the development unit that causes toner to drop on the transfer belt.