Physical damage to the thermistor’s wire harness or a loose connector (usually CNxxx on the fuser or controller board) creates an intermittent signal.
Before you begin: Turn off the printer, unplug the power cord, and allow the fuser to cool for at least 30 minutes. These components operate at over 350°F (180°C). sc569-00 ricoh
After repairing the root cause (e.g., replacing the fuser or thermistor), the code will persist in memory until manually reset. Physical damage to the thermistor’s wire harness or
The thermistor connects to the printer’s I/O board via a thin wire harness. If this cable is pinched, frayed, or partially unseated from the fuser connector, resistance changes cause false edge-temperature readings. unplug the power cord