Ricoh SC620–SC674 ADF, Finisher, Counter & Controller Communication Errors Explained

The SC620 through SC674 codes span several internal communication systems: the document feeder, finisher, paper banks, accounting/counter devices, remote service modem, and engine startup sequence. Sourced from Ricoh's official service manual.

Document Feeder (ADF) Communication Errors (SC620)

SC620-01 through -04 all mean the main board lost communication with the document feeder after it was initially recognized at startup. Common causes: a loose ADF connector, a damaged harness, electrical noise interference, or in the case of SC620-03 specifically, an unsupported/incompatible ADF model connected. Reconnecting the ADF cable resolves a meaningful share of these.

Finisher and Paper Bank Communication Errors (SC621–SC623)

• SC621-00: Lost communication with the finisher
• SC622-01/11/12/31: Lost communication with paper bank 1 (the specific sub-code depends on which paper feed unit model is installed)
• SC623-00: Communication failure between stacked paper banks/LCITs (specifically when one bank tries to recognize another below or above it)

Across this whole group, the fix path is the same: reconnect the relevant interface cable, check the harness for damage, and only replace a board if the simpler checks don't resolve it.

Counter and Authentication Device Errors (SC632–SC637)

• SC632/633: The optional accounting/counter device isn't responding over its serial connection — usually a disconnected or damaged line, fixed with a power cycle and connection check
• SC634/635: The counter device's backup RAM or backup battery has failed and needs replacing
• SC636-01/02: An IC card authentication module is missing, corrupted, or running the wrong version — relevant only if you have expanded authentication/ID card login set up
• SC637-01/02: A usage-tracking notification failed, either due to an app-level error or a failed connection to the tracking management server

Internal Board Communication Errors (SC663–SC669)

This is a large block of deep, internal firmware/ASIC-level communication codes (board resets, internal memory access errors, version mismatches between internal processing modules). These are genuinely obscure even by SC-code standards — they almost always point to a specific circuit board needing replacement, identified by a technician using internal diagnostic tools rather than anything a business owner could meaningfully troubleshoot. If you're seeing an SC66x code, this is a call-a-technician situation from the start.

Remote Service / RC Gate Modem Errors (SC650–SC653)

These relate to Ricoh's @Remote monitoring system, not your everyday printing or copying:

• SC650-01/04/05/13/14: Various dialup or modem configuration failures for the RC Gate remote monitoring connection
• SC651-01/02: Logged software errors during a remote dial-up attempt — these are logging-only and don't typically require action
• SC652/653: An authentication ID mismatch in the remote service setup, usually resolved by reinstalling the RC Gate certificate

If you're not using Ricoh's remote monitoring service at all, these codes are unlikely to come up, and if they do, they generally don't affect your ability to print or copy.

Engine Startup and Controller Errors (SC670, SC672–SC674)

• SC670-01 through -05: The print engine or its connection to the controller failed to come up correctly at startup or after returning from energy-saving mode — usually points to the BICU or controller board
• SC672-00 through -21: Controller/operation panel startup errors — covered in detail in our dedicated SC672 guide, including the two specific sub-codes that point at a single part: SC672-20 means the USB cable specifically, SC672-21 means the controller board specifically
• SC673-01: The Smart Operation Panel's internal monitor service crashed — a power cycle resolves this
• SC673-10: Communication between the Smart Operation Panel and the main machine isn't enabled in settings — fixed via a specific SP setting that a technician can flip rather than a hardware swap
• SC674-01/02: An internal video/image data transfer error on the controller board, usually cleared with a power cycle

Is It Worth Repairing, or Time to Replace?

Most of this group is board-level (BICU, controller, Imaging IOB) rather than a simple part swap, so expect real diagnostic time at a typical shop labor rate of around $350 per hour before parts even come into the picture. On an older machine, it's worth getting an honest opinion before committing to board-level repairs.

Not sure which way to go? Text us a photo of your error screen and tell us your model — we'll give you an honest read on whether it's worth fixing, no obligation. And if it makes more sense to replace it, we carry low-meter, fully tested copiers at wholesale liquidation pricing with free delivery and installation throughout Southern California, often available the same week.

📕 More info: Call or Text: 714-696-6082

Need a replacement copier instead of a repair? Browse our color copier inventory or black and white copier inventory at wholesale liquidation pricing.