If your Konica Minolta bizhub C454 displays a Jam Code 11-02, you are dealing with a specific timing synchronization fault related to paper from Tray 1. This error indicates that while paper successfully fed and reached the registration sensor, its arrival was too late for the machine’s precise internal clock. The paper did not form a sufficient “loop” or slack before the registration rollers began to accelerate it for imaging. This code is often a symptom of subtle mechanical wear or sensor degradation rather than a complete failure. This guide provides the systematic procedure technicians use to restore the critical timing between paper arrival and registration drive.

Understanding Jam Code 11-02

• Jam Type: Misfeed at the Tray 1 feed section due to a paper arrival delay at the registration assembly.
• Technical Definition: For paper fed from Tray 1, due to a delay in paper arrival, loop forming in front of the registration roller is not complete before the rise timing of the registration motor (M24). The paper is physically present but “out of sync.”
• Key Insight: This jam code points specifically to a delay after initial pick-up but before the registration rollers take over. The paper is moving too slowly on its journey to the registration point. The primary suspects are worn feed rollers, a dragging paper path, or a sluggish registration sensor (PS1) signal.
• Common User Experience: Paper from Tray 1 feeds partway into the machine and often triggers a jam just as it seems to be nearing the imaging area. You might notice the paper appears to pause or move hesitantly before the machine stops. The error is intermittent, occurring more often with heavier paper or full-capacity trays.

Relevant Parts & Systems

The fault lies in the components responsible for transporting the paper from the tray pick-up point to the registration rollers at a consistent, expected speed.

• Registration Sensor (PS1): The timer for this code. A sensor with a sluggish mechanical response or degraded electrical signal can report the paper’s arrival microseconds too late, causing the machine to perceive a delay.
• Tray 1 Feed Rollers & Separation Pad: Worn, glazed, or contaminated rollers cannot impart full driving force to the paper, causing it to travel slower than designed.
• Paper Feed Motor (M22): Drives the Tray 1 feed mechanism. If it is underpowered, intermittently stalling, or receiving incorrect voltage, feed speed will be inconsistent.
• Registration Motor (M24): Its “rise timing” is the fixed event the paper arrival is measured against. If M24 is faulty and activates erratically, it can cause a false timing mismatch.
• Tray 1 Paper Feed Clutch (CL3): If it engages weakly or slips, the initial “push” to the paper may be insufficient.
• Control Boards (FRB, EXCB, PRCB): The EXCB controls motor speeds. A faulty FRB can delay the PS1 signal. The PRCB calculates the timing window. Issues here can disrupt the synchronized sequence.

Step-by-Step Troubleshooting Procedure

⚠️ Safety First: Always turn OFF and unplug the copier before performing any internal inspection, testing, or part replacement.

Step 1: The Initial Check & Path Inspection

Focus on mechanical drag and wear.

1. Clear & Inspect: Open the right door and remove Tray 1. Visually inspect the entire paper path from Tray 1 to the registration rollers. Look for and remove any obstructions, torn paper fragments, or accumulated debris that could slow the sheet.
2. Paper & Tray Test: Switch to a fresh ream of standard 75-80gsm paper. Ensure it is properly loaded and the tray side guides are not too tight, creating drag. Overfilled trays can also slow the initial pick-up.
3. Roller Condition: Critically examine the Tray 1 pick-up roller and separation pad. Shiny, smooth, or cracked rollers must be replaced. Clean them first with a mild alcohol wipe as a temporary test.

Step 2: Check the Registration Sensor (PS1) I/O & Response

A delayed signal from PS1 is a leading cause of 11-02.

1. Locate the Registration Sensor (PS1). Manually flick its actuator flag rapidly with your finger. It must snap back quickly and without hesitation. Clean around the pivot point.
2. Perform an electrical I/O check at FRB CN8-3. Use a multimeter to monitor the voltage change while actuating the sensor. The change must be instant and clean. A slow transition (e.g., voltage drifting) indicates a failing sensor that is reporting the paper’s position late. Replace PS1 if any sluggishness is detected.

Step 3: Check the Tray 1 Feed Clutch (CL3) Operation

Ensure the initial feed engagement is strong and positive.

1. Listen for the clutch engagement when starting a print from Tray 1. It should be a sharp, definitive “click.”
2. Check the control signal at PRCB CN26-8. A strong signal with a weak mechanical response indicates a worn clutch that may be slipping, failing to give the paper a consistent initial speed. Replace CL3 if suspect.

Step 4: Check Motor Operations (M22, M24)

Motor performance is critical for timing.

1. Paper Feed Motor (M22): This motor’s speed directly controls how fast paper travels to the registration area. Check its control signals at EXCB CN3, pins 5-8. Listen for uneven humming or straining. A tired M22 will cause chronic 11-02 jams, especially under load. Consider replacement.
2. Registration Motor (M24): Verify its operation is smooth and consistent. Check signals at EXCB CN3, pins 1-4. A jerky or uneven M24 can create an erroneous “rise timing” reference, triggering the jam. Swap with a known good motor if possible to test.

Step 5: Advanced Control Board Diagnostics

If mechanical components are good, the timing calculation is faulty.

1. Replace the Front Side Board (FRB): If PS1 tests good but the signal reaching the main logic is delayed, the FRB is the intermediary. Replacing it is a common fix for persistent 11-02 codes after sensor replacement.
2. Expansion Control Board (EXCB) Check: This board governs motor speed. Perform a conduction check on the motor driver chips IC4 and IC5. Degraded drivers can cause M22 and M24 to run slightly off-specification speed, throwing off the entire paper transit timing. EXCB replacement is often necessary.
3. Printer Control Board (PRCB) Check: As the system timer, a fault here can shrink the acceptable timing window. Check the conduction of ICP5. PRCB replacement is the final step after confirming all other components are within specification.

Pro Tips for Prevention

• Preventive Replacement: Include feed rollers (especially for high-volume trays) in your periodic maintenance kits. Don’t wait for them to fail completely.
• Sensor Maintenance: Regularly clean PS1 and the paper path sensors to ensure crisp, immediate signaling.
• Firmware Updates: Ensure the machine has the latest firmware. Manufacturers sometimes release updates that adjust timing tolerances for known wear characteristics.
• Environment & Paper: Avoid humid environments that can cause paper to drag. Use recommended paper weights; heavy stock will naturally feed slower and is more likely to trigger 11-02 if components are even slightly worn.

When to Call a Professional

Jam Code 11-02 is a classic sign of mid-life wear in a copier. While a skilled user can often resolve it by replacing the Tray 1 pick-up roller and cleaning the registration sensor, pinpointing the exact delay often requires technical experience. If the jam persists after replacing rollers and PS1, the diagnosis moves into motor performance and board-level timing—areas best handled by a certified Konica Minolta technician. They can perform live system checks to measure sensor response times and motor speeds, ensuring an accurate and cost-effective repair.