• Code: 610
• Description: High temperature, low temperature, or high humidity that goes out of bounds is detected.
• Causes: • SENSOR HUM • HARNESS ASSY HUM • PWBA OHP SNR • HARNESS ASSY OHP SNR • HARNESS ASSY OHP • PWBA MCU
• Remedy: 1 Check after turning the power OFF and ON Does the error recur even when the power is turned off and back on again? Go to Step [2]. End of procedure 2 Check the connection of the PWBA OHP SNR Check the connection state between PWBA OHP SNR and PWBA MCU. Are P/J2411, P/J241, and P/J24 connected correctly? Go to Step [3]. Reconnect P/J2411, P/J241, and P/J24 correctly. 3 Check the continuity of the HARNESS ASSY OHP SNR Is the continuity between P/J2411 <=> P/J241 normal? Go to Step [4]. Replace the HARNESS ASSY OHP SNR. 4 Check the continuity of the HARNESS ASSY OHP Is the continuity between P/J241 <=> P/J24? Go to Step [5]. Replace the HARNESS ASSY OHP. 5 Replace of the PWBA OHP SNR Replace the PWBA OHP SNR. Was the trouble fixed? End of procedure Go to Step [6]. 6 Replace of the PWBA MCU Replace the PWBA MCU. Was the trouble fixed? End of procedure Go to Step [7]. 7 Check the connection of the SENSOR HUM Check the connection state between SENSOR HUM and PWBA MCU. Are P/J261 and P/J26 connected correctly? Go to Step [8]. Reconnect P/J261 and P/J26 correctly. 8 Check the continuity of the HARNESS ASSY HUM Is the continuity between P/J261 <=> P/J26 normal? Go to Step [9]. Replace the HARNESS ASSY HUM. 9 Check the power voltage supply to SENSOR HUM. Measure the voltage between PWBA MCU ground <=> P/J26-4PIN. Is the power voltage (approx. +5 V) output? Replace the SENSOR HUM. Replace the PWBA MCU.

• Code: 900
• Description: NV-RAM in the PWBA MCU error
  - Communication error between the PWBA MCU and the PWBA EEPROM, CRUM in the FUSER UNIT, CRUM in the TRANSFER UNIT, or the HVPS.
• Causes: • PWBA MCU • PWBA EEPROM XPRO • FUSER UNIT • TRANSFER UNIT
• Remedy: 1 Check after turning the power OFF and ON Does the error recur even when the power is turned off and back on again? Go to Step [2]. End of procedure 2 Check after reinstalling the PWBA MCU Remove the PWBA MCU, and reinstall it properly. Does the error still occur after the replacement? Replace the PWBA MCU. End of procedure

• Code: 901
• Description: Firmware error
• Causes: • PWBA MCU
• Remedy: 1 Check after turning the power OFF and ON. Does the error recur even when the power is turned off and back on again? Go to Step [2]. End of procedure 2 Check the firmware version Is the firmware version latest? Go to Step [3]. Update the firmware. 3 Check after reinstalling the PWBA MCU Remove the PWBA MCU, and reinstall it properly. Does the error still occur after the replacement? Replace the PWBA MCU. End of procedure

• Code: 998
• Description: Engine communication error
• Causes: • HARNESS ASSY ESS • BOARD ASSY, MAIN • PWBA MCU
• Remedy: 1 Check the firmware version of the PWBA MCU Check the firmware version of the PWBA MCU. Is the version latest? Go to Step [2]. Update the firmware and go to step [2]. 2 Check the firmware version of the BOARD ASSY, MAIN Check the firmware version of the BOARD ASSY, MAIN. Is the version latest? Go to Step [3]. Update the firmware. 3 Check the continuity of HARNESS ASSY ESS 1. Disconnect P10 on the PWBA MCU. 2. Disconnect the CN601 on the BOARD ASSY, MAIN 3. Check each wiring for continuity. Do all of the wiring have normal continuity? Go to Step [4]. Replace the HARNESS ASSY ESS. 4 Replace the BOARD ASSY, MAIN Replace the BOARD ASSY, MAIN. Does the error still occur after the replacement? Replace the PWBA MCU. End of procedure