Error Code C1102 is a Finisher Main Tray Up/Down Motor Drive Malfunction on Konica Minolta bizhub machines with an optional finisher installed. It fires when the finisher’s main exit tray fails to move to its expected position — either failing to rise during a lift cycle or failing to lower when commanded — and the confirmation sensor or switch does not register the expected position change within the allowed time.

What makes C1102 distinctly different from standard paper tray errors (like C0202) is that it involves the finisher output tray — the large motorised tray that collects finished output sets and rises and falls to maintain the correct paper delivery height as the stack grows. This tray uses a sophisticated multi-sensor position detection system, and the exact components involved differ significantly between the FS-533 (inner finisher) and the FS-534 / FS-535 / FS-526 (floor/side finishers).

C1102 Has Completely Different Components Depending on Your Finisher

This is the most important thing to understand about C1102. The motor, sensors, and detection logic differ fundamentally between finisher models. Diagnosing the wrong components wastes significant time. Identify your installed finisher before starting any diagnosis.

Exact Detection Conditions by Finisher Model

FS-533 (Inner Finisher)

• Lift-up failure: While the exit tray is being lifted, the stapler movement motor (M107) is not UNBLOCKED (does not move to clear position) after the set period of time has elapsed after the tray lift up motor (M109) is turned ON
• Descent failure: While the exit tray is being lowered, the stapler movement motor (M107) is not BLOCKED (does not return to home) after the set period of time has elapsed after M109 is turned ON

FS-534 / FS-534SD (Side/Floor Finisher)

• Lift-up failure: While the exit tray is being lifted, the main tray upper position sensors (PS26/PS27) are not blocked AND the main tray upper position detect switch (SW2) is not turned ON, even after the main tray up/down motor (M11) turns by the set number of pulses
• Descent/full detection failure: While the exit tray is being lowered, the main tray full detection sensor (PS29) is not blocked after the set period of time has elapsed after M11 is turned ON

FS-535 (Large Floor Finisher)

• Lift-up failure: The main tray upper limit sensors (PS44/PS45) are still ON after the set period of time has elapsed while the main tray up/down motor (M5) is energised
• Descent failure: The staple paper exit top surface sensor (PS7) is unblocked after the set period of time has elapsed while M5 is energised

FS-526 / FS-527 (Older Floor Finisher)

• The main tray top surface sensor (PS4) is turned neither ON nor OFF after the set period while M5 is energised
• The staple paper exit top surface sensor (PS7) is turned neither ON nor OFF after the set period while M5 is energised

All Exact Connector and Signal References

Common Causes of Error Code C1102

• Physical obstruction in the tray lift mechanism — the most common cause across all finisher models. A foreign object (paper clip, staple, torn paper fragment, pen) fallen into the tray lift track prevents the tray from completing its travel in either direction. The motor runs but the tray physically cannot move far enough to trigger the position sensors
• Exit tray manually pushed out of position — the finisher exit tray is sometimes manually repositioned by users when removing output. If pushed too far up or down, the tray can be outside the normal travel range when the next job starts, causing the lift cycle to fail immediately
• Tray lift drive belt slipped or broken (FS-534) — the large floor-standing FS-534 uses a drive belt to move the main output tray vertically. A slipped or broken belt means M11 runs but the tray does not move. Field technicians consistently report this as one of the most common hardware causes of C1102 on FS-534 installations — particularly checking the lower gear attached to the belt drive
• Loose or disconnected motor or sensor connector — the connectors between M109/M11/M5 and the FSCB, or between the position sensors and the FSCB, have worked loose. A loose connector on any one of these components produces the same C1102 symptom as the component itself failing
• Worn or cracked tray lift drive gear (FS-534) — the gear that connects M11 to the belt drive has cracked or a tooth has stripped. M11 spins but the drive coupling to the belt is broken. The lower gear at the bottom of the lift assembly is particularly prone to cracking at its mounting pin
• Failed position sensor (PS107, PS26, PS27, PS29, PS44, PS45, PS4, PS7) — a sensor whose photo-interrupter has failed, or whose actuator flag is bent or broken, cannot confirm tray position even when the tray physically reaches the correct location
• Failed detect switch SW2 (FS-534) — the mechanical switch that confirms the tray has reached the upper limit has failed or its actuator is not being depressed correctly because the tray is not reaching the full upper position
• Failed tray lift motor (M109/M11/M5) — the motor itself has worn bearings or a failed winding. Less common than mechanical and connector causes but confirmed by a motor that does not respond to the service mode operation check
• Paper stack overflow — tray full condition not detected (FS-534/FS-535) — the tray has filled beyond its capacity and the full-detection sensor (PS29/PS7) has not triggered. The tray cannot descend because it is overfull. Always check whether the output tray is full or overloaded before starting any electrical diagnosis
• Faulty FSCB — the finisher control board cannot correctly drive the lift motor or read the position sensors — last resort after all mechanical and connector causes are ruled out

Step-by-Step Troubleshooting Procedure

Step 1 — Check for Physical Obstructions and Tray Position

This step resolves the majority of C1102 cases in office environments and takes under two minutes.

1. Open the finisher access cover(s) and visually inspect the exit tray lift mechanism:
   • Look in the tray lift track/rails on both sides for foreign objects — paper clips, staples, pieces of torn paper, pens
   • Look underneath and around the tray for anything preventing free vertical movement
2. Check whether the finisher output tray is overloaded — remove all paper from the tray and check if C1102 clears after a power cycle. An overloaded tray prevents the tray from descending (FS-534/FS-535) and can cause C1102 on the full-detection direction
3. Manually attempt to move the exit tray up and down by hand (with the machine powered OFF):
   • The tray should move freely in both directions with even, smooth resistance
   • Any binding, grinding, hard stops at a specific point, or the tray feeling stuck at one end of travel indicates a mechanical obstruction or drive component failure
4. On the FS-534 specifically: with the finisher access covers open, look for the drive belt on the vertical lift assembly. Confirm the belt is intact and has correct tension. Check the lower gear where the belt engages — a cracked gear hub or a gear that has come off its shaft is a common finding on high-volume FS-534 installations
5. Remove any foreign objects found, clear any obstruction, and power cycle the machine. If C1102 clears, run a test print with stapling to confirm the tray cycles correctly through several output sets

Step 2 — Check and Reseat All Motor and Sensor Connectors

Loose connectors are the leading electrical cause of C1102 across all finisher models. Use the model-specific references in the table above to reseat the correct connectors for your finisher.

For FS-533:

1. Power OFF and unplug the machine
2. Access the FS-533 control board (FSCB) — typically inside the finisher unit behind a cover panel
3. Reseat: M109 → FSCB CN108 (tray lift motor connector)
4. Reseat: PS107 → FSCB CN110 (exit tray home sensor connector)
5. Also reseat the M107 (stapler movement motor) connector — M107’s state is used to confirm tray position on the FS-533, making it part of the C1102 detection chain

For FS-534 / FS-534SD:

1. Power OFF and unplug the machine
2. Access the FSCB inside the FS-534
3. Reseat: M11 → FSCB J9<A> (main tray up/down motor — pins 9 to 10)
4. Reseat: PS26 → FSCB J14<A> (upper position sensor/R — pin 5)
5. Reseat: PS27 → FSCB J14<B> (upper position sensor/F — pin 8)
6. Reseat: PS29 → FSCB J14<A> (full detection sensor — pin 8)
7. Reseat: SW2 → FSCB J10 (upper position detect switch — pins 1 to 2)
8. Inspect all pins for oxidation, bent contacts, or backed-out pins — clean with electrical contact cleaner if oxidized

For FS-535 / FS-526 / FS-527:

1. Power OFF and unplug the machine
2. Reseat M5 motor connector at FSCB
3. Reseat PS44, PS45, PS7 (FS-535) or PS4, PS7 (FS-526/527) sensor connectors at FSCB
4. Inspect all pins carefully

Step 3 — Perform Position Sensor I/O Checks in Service Mode

The sensor check immediately tells you whether the tray is physically reaching its positions but sensors are not detecting it, or whether the tray is genuinely not moving. This is the most important diagnostic step before replacing any component.

For FS-534:

1. Enter Service Mode and navigate to the finisher sensor I/O check section
2. Monitor PS26 at FSCB J14<A>-5 (ON), Location: FS-534 2-C
3. Monitor PS27 at FSCB J14<B>-8 (ON), Location: FS-534 3-C
4. Manually push the exit tray fully upward by hand (power OFF for safety) — both PS26 and PS27 should switch to ON simultaneously when the tray reaches the upper limit
5. Monitor PS29 at FSCB J14<A>-8 (ON), Location: FS-534 4-C — this sensor should change state when the tray reaches the lower/full position
6. Monitor SW2 at FSCB J10-1 to 2, Location: FS-534 8-K — SW2 must also activate at the upper limit. If PS26/PS27 switch but SW2 does not, the tray is not reaching the mechanical switch contact point or SW2 has failed

For FS-533:

1. Monitor PS107 at FSCB CN110, Location: FS-533 7-D to E
2. Manually move the tray from standby to the output position — PS107 should switch state
3. If PS107 does not switch when the tray physically reaches position, replace PS107

Interpreting sensor results:

• Sensors switch correctly when tray is manually positioned: The tray mechanism is functional — the motor is not moving the tray far enough. Check the drive belt (FS-534) and drive coupling before replacing the motor
• Sensors do not switch even when tray physically reaches position: Sensor has failed or its actuator flag is bent/missing. Replace the affected sensor
• SW2 does not actuate even when PS26/PS27 confirm upper position (FS-534): The tray is reaching the sensor level but not the physical switch contact point — inspect for drive belt stretch or a worn tray carrier that is stopping slightly short of the full upper limit

Step 4 — Inspect the Tray Lift Drive Belt and Gear Assembly (FS-534 — Critical Step)

For the FS-534 and FS-534SD, this step is uniquely important and resolves a large proportion of hardware C1102 cases. The tray lift mechanism uses a belt-and-gear drive that is subject to wear and mechanical failure.

1. With the finisher front and rear access covers open, locate the vertical tray lift assembly — the mechanism that runs on both sides of the tray
2. Inspect the drive belt on both sides:
   • Look for a belt that has slipped off its pulleys — the belt should be seated squarely on both the upper and lower pulleys
   • Look for a broken or cracked belt — a belt that has snapped means M11 runs but the tray does not move at all
   • Check belt tension — an excessively loose belt slips under load and causes intermittent C1102
3. Inspect the lower gear at the bottom of the lift assembly — this gear connects M11 to the belt drive. Field technicians consistently report this as a failure point:
   • Look for a crack running through the gear hub at the mounting pin location
   • Check whether the gear is firmly locked to its shaft — a gear that spins freely on the shaft means M11 runs but drives nothing
   • Inspect for stripped teeth, particularly on the first gear in the M11 drive train
4. If the belt is intact and correctly tensioned but the lower gear is cracked — replace the gear. On many FS-534 units this gear is available individually and resolves C1102 without motor or FSCB replacement
5. If the belt is slipped — reseat it on both pulleys, confirm correct tension, and test. If it slips again immediately, the belt is stretched and must be replaced

Step 5 — Perform the Motor Operation Check in Service Mode

After confirming sensors and mechanical drive components, use service mode to directly command the lift motor and verify its response.

For FS-534:

1. Enter Service Mode → finisher motor operation check section
2. Command M11 to run: FSCB J9<A>-9 to 10, Location: FS-534 10-C to D
3. The motor should run immediately and the tray should begin moving
4. If M11 runs but tray does not move → mechanical drive fault (belt/gear) — return to Step 4
5. If M11 does not respond to the operation check with a confirmed drive signal present → M11 has failed internally → replace M11

For FS-533:

1. Command M109 to run: FSCB CN108, Location: FS-533 10-E
2. The tray lift mechanism should actuate immediately
3. If M109 runs but PS107 still does not change state → PS107 sensor flag issue → inspect and replace PS107
4. If M109 does not run with a confirmed signal → replace M109

Step 6 — Replace Failed Components

Based on the findings from Steps 1–5, replace the specific failed component:

Replace the tray lift motor (M109 / M11 / M5) when the motor operation check confirms the drive signal is present at the motor connector but the motor does not respond:

1. Order the correct replacement motor for your specific finisher model — motor part numbers differ between FS-533, FS-534, and FS-535
2. Power OFF and unplug. Note motor mounting orientation before removal
3. Disconnect the harness, remove mounting screws, extract the motor
4. Install the replacement, ensure coupling engages correctly with the drive gear, reconnect harness
5. Run the motor operation check in service mode before closing finisher panels

Replace a failed position sensor (PS107, PS26, PS27, PS29, PS44, PS45, PS4, PS7) when the I/O check confirms the sensor does not switch state when its actuator flag physically enters the sensor beam:

1. Before replacing the sensor, confirm the actuator flag on the tray carrier or tray arm is intact and correctly aligned — a bent or missing flag cannot trigger any sensor regardless of the sensor’s condition
2. Locate the failed sensor on the finisher tray assembly frame
3. Disconnect the harness, remove the mounting screw(s), and fit the replacement sensor
4. Confirm correct switch direction in the service mode I/O check before closing covers

Replace the upper position detect switch SW2 (FS-534) when the sensor I/O check shows PS26/PS27 switching correctly but SW2 does not activate at the full upper limit:

1. Locate SW2 on the FS-534 tray lift assembly — it is a mechanical micro-switch at the top of the tray travel
2. Before replacing, confirm the tray carrier arm is physically reaching and depressing the switch actuator — if the arm stops just short of the switch, the drive belt or gear is slipping and SW2 is not the fault
3. Replace SW2 if the arm confirms correctly reaches the switch but the switch does not click

Step 7 — Replace the FSCB (FS Control Board)

Replace the FSCB only after all mechanical components (drive belt, gears, tray path), all connectors, all sensors, and the motor have been confirmed good — and C1102 still persists.

1. Access the FSCB inside the finisher unit
2. Disconnect all harnesses from the FSCB, noting their positions before removal
3. Remove the FSCB mounting screws and extract the board
4. Install the replacement FSCB and reconnect all harnesses
5. After installation, update the FSCB firmware to the current version — replacement boards often ship with older firmware
6. Run a full test job including stapling and multi-set output to confirm the tray lift cycles correctly through multiple sets

Quick Reference — Troubleshooting by Symptom

Understanding C1102 Within the C110x Finisher Error Family

C1102 belongs to a group of finisher motor drive errors that all share the same detection logic — a motor is commanded to run and a position confirmation sensor or switch does not change state within the allowed time. Understanding the family helps identify shared causes when multiple codes appear together:

• C1102 — Main tray up/down motor drive malfunction (M109/M11/M5)
• C1103 — Alignment motor/Front drive malfunction (paper alignment mechanism)
• C1105 — Stacker plate drive motor malfunction (FS-540 only)
• C1106 — Bundle eject motor drive malfunction
• C1109 — Stapler motor drive malfunction
• C1112 — Punch motor malfunction
• C1113 / C1114 — Tray shift motor malfunction

C1102 and C1103 appearing simultaneously points to a power supply issue inside the finisher or a failing FSCB — both the tray lift and alignment motors are controlled by the same FSCB, and a board-level power fault affects multiple motors at once.

C1102 alongside C1004 (FNS communication error) means the finisher has both a communication failure with the main machine AND a tray lift fault — fix C1004 (communication) first, as an unstable communication link can cause false motor malfunction codes to fire on subsequent operations.

Preventing C1102 From Recurring

• Inspect the finisher tray lift path during every PM visit — paper clips, staples, and torn media fragments in the tray lift track are the most common cause of C1102 in office environments. A 3-minute visual inspection and clearance during PM prevents these calls entirely
• Inspect and reseat tray lift motor and sensor connectors during PM — these connectors are subject to vibration from the tray’s continuous cycling. A 60-second reseat during routine maintenance prevents connector-related C1102 events
• Check the FS-534 drive belt condition during PM on high-volume machines — the belt stretches over high page counts and begins to slip before it breaks completely. On machines running above 50,000 pages per month through the finisher, inspect the belt tension at every major PM and replace proactively when it shows signs of stretch
• Check the FS-534 lower gear at the belt drive during PM — the lower gear cracking at its mounting pin is a common age-related failure on high-volume FS-534 installations. Inspecting and replacing this gear proactively costs significantly less than an emergency service call for C1102
• Advise users not to manually force the output tray — the finisher exit tray should never be manually pushed up or down with force. Users sometimes do this when removing large stacks of output, which can misalign the tray position sensors or stress the belt and gear assembly. A simple user instruction prevents a recurring cause of C1102
• Always update FSCB firmware after replacement — a replacement FSCB with outdated firmware can produce C1004 and C1102 on the first startup. Make firmware update a mandatory final step after any FSCB board replacement

Professional Technician Summary

Error Code C1102 on Konica Minolta bizhub machines is a finisher main tray lift failure, and its root cause varies significantly depending on which finisher is installed. The most important diagnostic rule is: identify your finisher model before touching any component — the FS-533, FS-534, and FS-535 use completely different motors, sensors, and detection logic for the same error code.

In field practice, physical obstructions in the tray lift path and tray drive belt/gear failures account for the majority of C1102 cases on FS-534 installations. For the FS-533 inner finisher, loose connectors at M109 and PS107 are the most common cause. For older FS-526/FS-527 floor finishers, sensor faults (PS4, PS7) after prolonged use are the typical hardware cause.

The service mode sensor I/O check is the fastest path to correct diagnosis — it tells you within minutes whether the tray is not reaching its target position (mechanical/motor fault) or whether it is reaching the position but sensors are not detecting it (sensor/connector fault). Perform this check before replacing any motor or sensor.

On the FS-534 specifically, always inspect the drive belt and lower gear before ordering a replacement motor. A cracked lower gear or slipped belt is far more common than a failed M11 motor and is significantly less expensive to replace.