All codes
Service call
SC320
Polygonal mirror motor (older numbering)
BLaser / write
Level B — stop, power-cycle may clear
First check
Same as SC201 on current IM C. Listen for polygon, replace LOSU.
What it means
Polygonal mirror motor (older numbering). Confirm the exact subcode against the FSM for this serial — meaning can shift by generation.
Aficio/early MP used 320 for polygon. IM C uses 201/202.
Likely causes
- Same as SC201 on current IM C. Listen for polygon, replace LOSU.
On-site steps
Parts to have on the truck
- Laser optics unit
Related codes
Confirm the subcode and part number in the FSM for this serial. Raicoh is a field companion, not a replacement for the book.