All codes
Service call
SC590
Exhaust / fusing fan motor
BFusingCommon field call
Level B — stop, power-cycle may clear
First check
Spin the fan by hand. Dust cake or a locked bearing.
What it means
Fusing or exhaust fan lock. Ignore this and you will get 541–545 next.
Likely causes
- Fan locked
- Harness
- Driver
On-site steps
Parts to have on the truck
- Fusing exhaust fan
- Main exhaust fan
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.