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. Check connection of the connector and the harness. 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: F3-22
Description: Paper feed tray 2 lift operation trouble LUD2 does not turn ON within the specified time
Causes: LUD2 does not turn ON within the specified time. CLUD2 sensor trouble. Paper feed tray 2 lift unit trouble. PCU PWB trouble. Harness and connector connection trouble.
Remedy: Check the harness and the connector of LUD2. Replace the lift-up unit. Replace the PCU PWB.
Code: H2-00
Description: Thermister open trouble (TH_UM_AD2)
Causes: Thermister trouble. PCU PWB trouble Connection trouble of the connector and the harness. Fusing unit not installed.
Remedy: Replace the thermistor. Replace the PCU PWB. Check connection of the connector and the harness.