• Code: 581-11
• Description: Fusing thermistor disconnection (low power). These SCs are detected if the machine detects the prescribed timing when: • The machine starts up. • The machine returns from the energy saver mode. • The machine stays in low power mode.
• Causes: • Thermopile disconnection (SC581-01) • Shorted fusing thermistor (SC581-02) • Loose connector
• Remedy: 1. Check the input voltage and replace the power plug (SC581-11/-12). 2. Reconnect the connectors between the fusing unit, fusing drawer connector, and BiCU. 3. Replace the fusing thermistor. 4. Replace the fusing unit. 5. Replace the harnesses between the BiCU and the fusing drawer connector. 6. Replace the BiCU. 7. Replace the AC controller board.

• Code: 581-12
• Description: Shorted fusing thermistor (low power). These SCs are detected if the machine detects the prescribed timing when: • The machine starts up. • The machine returns from the energy saver mode. • The machine stays in low power mode.
• Causes: • Thermopile disconnection (SC581-01) • Shorted fusing thermistor (SC581-02) • Loose connector
• Remedy: 1. Check the input voltage and replace the power plug (SC581-11/-12). 2. Reconnect the connectors between the fusing unit, fusing drawer connector, and BiCU. 3. Replace the fusing thermistor. 4. Replace the fusing unit. 5. Replace the harnesses between the BiCU and the fusing drawer connector. 6. Replace the BiCU. 7. Replace the AC controller board.

• Code: 591-01
• Description: Pressure roller thermistor (front) disconnection. • Pressure roller thermistor (front) detects a temperature of -11 degrees C or less for 20 consecutive seconds when the fusing lamp is activated.
• Causes: • Thermistor disconnection • Loose connector
• Remedy: • Reconnect the connectors between the fusing unit, fusing drawer connector, and BiCU. • Replace the thermistor. • Replace the fusing unit. • Replace the harnesses between the BiCU and the fusing drawer connector. • Replace the BiCU. • Replace the AC controller board.

• Code: 591-11
• Description: Pressure roller thermistor (front) disconnection (low power). • Pressure roller thermistor (front) detects a temperature of -11 degrees C or less for 20 consecutive seconds when the fusing lamp is activated.
• Causes: • Thermistor disconnection • Loose connector
• Remedy: • Reconnect the connectors between the fusing unit, fusing drawer connector, and BiCU. • Replace the thermistor. • Replace the fusing unit. • Replace the harnesses between the BiCU and the fusing drawer connector. • Replace the BiCU. • Replace the AC controller board.

• Code: 592-02
• Description: Pressure roller thermistor (front) cannot be reloaded
• Causes: • Dirty or deformed thermistor • Input voltage out of specification (out of warranty) • Fuse blown out
• Remedy: • Check the input voltage and replace the power plug. • Replace the fusing thermostat • Replace the fusing lamp. • Replace the thermistor. • Replace the BiCU. • Replace the AC controller board.

• Code: 592-12
• Description: The machine temperature does not reach a temperature of 50 degrees C when 100 seconds passes after starting a job where the paper width is wider than 206 mm AND is equal or smaller than 216 mm.
• Causes: • Dirty or deformed thermistor • Input voltage out of specification (out of warranty) • Fuse blown out
• Remedy: • Check the input voltage and replace the power plug. • Replace the fusing thermostat • Replace the fusing lamp. • Replace the thermistor. • Replace the BiCU. • Replace the AC controller board.

• Code: 593-00
• Description: Pressure roller thermistor (front) high temperature (soft) Pressure roller thermistor (front) detects a temperature of 230 degrees C for consecutive 10 times when the fusing lamp is activated.
• Causes: • Shorted triac • IOB error • BCU error
• Remedy: • Reconnect the connectors between the fusing unit, fusing drawer connector, and BiCU. • Replace the thermistor. • Replace the harnesses between the BiCU and the fusing drawer connector. • Replace the BiCU. Replace the fusing unit if all the above steps cannot resolve the issue.

• Code: 594-00
• Description: Pressure roller thermistor (front) High temperature (hard) Pressure roller thermistor (front) detects the prescribed temperature.
• Causes: • Shorted triac • IOB error • BCU error • Fusing unit: out of control
• Remedy: • Reconnect the connectors between the fusing unit, fusing drawer connector, and BiCU. • Replace the thermistor. • Replace the harnesses between the BiCU and the fusing drawer connector. • Replace the BiCU. Replace the fusing unit if all the above steps cannot resolve the issue.