• Code: F2 90
• Description: Half-tone process limit error
• Causes: The difference between the correction value after execution of half-tone process control and the previous correction value exceeds the specified max. value of each color. <The error is recorded in the trouble history, but F2 trouble is not indicated on the display and the previous correction value is remained.>
• Remedy: Common Check Use SIM 44-2 to adjust the process control sensor gain. Case 1 Cause When "Error" occurs in the gain adjustment of SIM 44- 2: 1. Disconnection of the harness between the PCU PWB and the image density sensor. 2. Image density sensor dirt/trouble. Check & Remedy 1. Check connection of the harness between the PCU PWB and the image density sensor. 2. Clean/replace the image density sensor. Case 2 Cause When SIM 44-2 gain adjustment is completed: Insufficient cleaning of the transfer belt, calibration plate solenoid operation trouble Check & Remedy Check the drum surface and the belt surface.

• Code: F3 12
• Description: Cassette 1 lift up trouble
• Causes: LUD1 does not turn on within the specified time.
• Remedy: Case 1 Cause LUD1 sensor trouble, disconnection of harness among the PCU PWB, the lift-up unit, and the paper feed unit. Check & Remedy Check LUD1, its harness, and the connector. Case 2 Cause Cassette 1 lift-up motor trouble Check & Remedy Check the lift-up unit.

• Code: F6 00
• Description: ICU-FAX communication trouble (ICU detection)
• Causes: Communication establishment error, framing, parity, protocol error
• Remedy: Case 1 Cause Slave unit PWB connector connection trouble. Slave unit PWB-ICU PWB harness trouble Check & Remedy Check connection between the slave unit PWB and the ICU PWB, and check the harness. Case 2 Cause Broken pin of the mother board connector of the slave unit PWB Check & Remedy Check the connector of the slave unit PWB. Case 3 Cause Slave unit ROM trouble/ No ROM/ Improper insertion of ROM/ ROM pin breakage Check & Remedy Check grounding of the main unit. Check the ROM of the slave unit PWB.

• Code: F6 01
• Description: FAX expansion flash memory abnormality (ICU detection)
• Causes: An expansion flash memory with SRAM backup data in it is installed.
• Remedy: Case 1 Cause SRAM backup data are detected in the expansion flash memory. The simulation function (SIM 66- 19) is provided to save SRAM backup data into an expansion flash memory. This trouble occurs when an expansion flash memory to which SRAM backup data are saved with the above function is installed. Check & Remedy Use SIM 66-20 to restore the backup data to the SRAM, and use SIM 66-10 to clear the expansion flash memory. If the data are unnecessary, simply clear the expansion memory with SIM 66-10.

• Code: F6 04
• Description: FAX MODEM operation abnormality
• Causes: FAX PWB MODEM chip operation trouble
• Remedy: Case 1 Cause Normal operation is made with the FAX PWB SW101 on the BOOT side. FAX PWB MODEM chip operation trouble Check & Remedy Set the FAX PWB SW101 to the other side than the BOOT side, and supply power again. Replace the FAX PWB.

• Code: F6 20
• Description: FAX write protect release
• Causes: The write protect JP of the ICU PWB is released.
• Remedy: Case 1 Cause The FAX write protect pin is set to Write Enable. Check & Remedy Check the write protect pin of the ICU PWB. Case 2 Cause ICU PWB trouble Check & Remedy Replace the ICU PWB. Case 3 Cause FAX PWB trouble Check & Remedy Replace the FAX PWB.

• Code: F6 21
• Description: Improper combination of the TEL/ LIU PWB and the FAX soft switch.
• Causes: Improper combination of the TEL/LIU PWB and the FAX PWB information (soft switch)
• Remedy: Case 1 Cause The destination of the installed TEL/LIU PWB differs. Check & Remedy Check the destination of the TEL/LIU PWB. Case 2 Cause The FAX PWB information (soft switch) differs. Check & Remedy Check the FAX PWB information (soft switch). Case 3 Cause TEL/LIU PWB abnormality Check & Remedy Replace the TEL/LIU PWB.

• Code: F6 97
• Description: The FAX-BOX PWB is not one for the AR-C172M. (FAX detection)
• Causes: The Modem controller of the FAX-BOX is not one for the AR-C172M.
• Remedy: Case 1 Cause The FAX-BOX Modem controller PWB information (hard detection) is not for the AR-C172M. (A Modem controller PWB for the ARFX5/ FX6 or the AR-FX8 is used.) Check & Remedy 1. Check the FAX-BOX MODEM controller. 2. Replace the MODEM controller PWB with one for the AR-C172M.