SRVO-123: Fan motor rev slow down
Early warning that a backplane cooling fan is spinning slow - the precursor to SRVO-014, which stops the CPU when the fan stops entirely.
What it means
Early warning that a backplane cooling fan is spinning slow - the precursor to SRVO-014, which stops the CPU when the fan stops entirely. The number identifies the fan: (1) above slot 1, (2) above slot 2, (3) both. This is the cheap moment to act.
Common causes
Ranked by what technicians most often find, most likely first.
- Fan bearing wearing out or dust-loaded fan slowing down.
- Fan cable degrading.
- Backplane or (rarely) main board fault.
How to fix it
- Check and replace the identified fan and its cable - treat this warning as a scheduled-maintenance trigger, because the next stage (SRVO-014) halts the CPU mid-production.
- If a fresh fan doesn't clear it, backplane unit next; image-backup before any main board work.