• Code: F2-74
• Description: Toner cartridge CRUM error (BLACK)
• Causes: Toner cartridge (CRUM) trouble. PCU PWB trouble. Connector/harness trouble.
• Remedy: Replace the toner cartridge. Replace the PCU PWB. Connector/harness trouble.

• Code: F2-75
• Description: Toner cartridge CRUM error (CYAN)
• Causes: Toner cartridge (CRUM) trouble. PCU PWB trouble. Connector/harness trouble.
• Remedy: Replace the toner cartridge. Replace the PCU PWB. Connector/harness trouble.

• Code: F2-76
• Description: Toner cartridge CRUM error (MAGENTA)
• Causes: Toner cartridge (CRUM) trouble. PCU PWB trouble. Connector/harness trouble.
• Remedy: Replace the toner cartridge. Replace the PCU PWB. Connector/harness trouble.

• Code: F2-77
• Description: Toner cartridge CRUM error (YELLOW)
• Causes: Toner cartridge (CRUM) trouble. PCU PWB trouble. Connector/harness trouble.
• Remedy: Replace the toner cartridge. Replace the PCU PWB. Connector/harness trouble.

• Code: F2-78
• Description: Registration image density sensor trouble (Transfer belt substrate reflection rate abnormality)
• Causes: Image density (registration) sensor trouble (Sensor sensitivity adjustment trouble). PCU PWB trouble. Connection trouble of the connector and the harness. Image density (registration) sensor dirt. Transfer belt dirt, scratch.
• Remedy: Replace the image density (registration) sensor. Replace the PCU PWB. Harness and connector connection trouble. Clean the image density (registration) sensor. Clean or replace the transfer belt.

• Code: F3-12
• Description: Paper feed tray 1 lift operation trouble
• Causes: LUD1 is not turned ON within the specified time. CLUD1 sensor trouble Paper feed tray 1 lift unit trouble. PCU PWB trouble. Harness and connector connection trouble.
• Remedy: Check connection of the harness and the connector of LUD1. Replace the lift-up unit. Replace the PCU PWB.

• Code: H2-00
• Description: Thermistor open trouble (TH_UM_AD2)
• Causes: Thermistor trouble. PCU PWB trouble Connection trouble of the connector and the harness. Fusing unit not installed.
• Remedy: Replace the thermistor. Replace the PCU PWB. Harness and connector connection trouble.

• Code: H2-01
• Description: Thermistor open trouble (TH_LM)
• Causes: Thermistor trouble. PCU PWB trouble. Connection trouble of the connector and the harness. Fusing unit not installed.
• Remedy: Replace the thermistor. Replace the PCU PWB. Harness and connector connection trouble.