🛠️ Konica Minolta bizhub i-Series: Resetting Error Code C-8402

Executive Summary: The C-8402 error on Konica Minolta i-Series models (C250i through C750i) indicates a Double Feed Detection Board (DFCB) Anomaly. This failure occurs within the Automatic Document Feeder (ADF) system—specifically the ultrasonic sensors—and requires a specific hardware-firmware synchronization to resolve.

🔍 1. Error Core Logic: What is C-8402?

This code is triggered when the communication between the ultrasonic transmitter and receiver (designed to detect two sheets of paper at once) fails.

  • System Location: Exclusively within the DF-632 Document Feeder; the main printer unit is rarely the cause.
  • Target Components: DFCB Control Board and the Receiver Board.

🛠️ 2. Official Repair & Replacement Protocol

Follow this order:

Phase 1: Primary Hardware Replacement

  • Part to Replace: DFCB Control Board.
  • Part Number: AAMNPP4902.
  • Success Rate: High. Replacing this board alone usually clears the C-8402 fault.

Phase 2: Secondary Hardware Replacement (If Error Persists)

  • Part to Replace: Receiver Board.
  • Part Number: AAMNPP5002.
  • Note: In stubborn cases, both the DFCB and Receiver boards must be replaced simultaneously to ensure signal synchronization.

Phase 3: MANDATORY Firmware Update

Replacing the hardware is only 50% of the fix. You must flash the following firmware versions to “marry” the new boards to the system:

  • Card Version: G00-N5
  • DF (Document Feeder) Firmware: G00-04

📍 3. Location & Installation Guide

  1. Access: Open the ADF top cover and lift the unit to expose the scanning glass.
  2. Position: The DFCB is located beneath the feed path, near the feed roller and separation pad.
  3. Removal:
    Disconnect the Flat Flexible Cable (FFC) and power cable first.
    Remove the retaining screws to extract the rectangular DFCB board (equipped with the ultrasonic sensor).
  4. Cleaning Tip: Before replacing, check for paper dust on the ultrasonic sensor “eyes,” as heavy debris can sometimes mimic a board failure.

📋 Technical Component Summary

Component Part Number Role
DFCB Board AAMNPP4902 Primary Control (Main Target)
Receiver Board AAMNPP5002 Signal Reception (Secondary Target)
System Firmware G00-N5 / G00-04 Critical for hardware recognition

 

🚀 Technical Meta Tags

  • Primary Category: Konica Minolta bizhub Service / i-Series Troubleshooting
  • Applicable Models: bizhub C250i, C300i, C360i, C450i, C550i, C650i, C750i.
  • Part Specifications: Ultrasonic Double Feed Detection, DFCB Board AAMNPP4902.
  • Firmware Requirements: Document Feeder G00-04 update.
  • Keywords: Konica Minolta C-8402 fix, bizhub i-Series error codes, replace AAMNPP4902, ADF double feed board failure.
  • Search Intent: How to reset C-8402 on Konica Minolta? Location of DF-632 double feed board. bizhub i-series firmware for C-8402.