Fanuc alarm SP9042: NO 1-ROT POSITION CODER DETECT
spindle alarm (serial spindle, alpha i) · Fanuc 0i-D
What it means
The one-revolution signal from the position coder was not detected. Orientation, rigid tap return and thread-cutting functions all depend on this reference and cannot proceed without it.
Likely causes
- Dead position coder or severed mark-channel conductor
- Unplugged JY-series connector at the SPM
- Coder disk mark obscured by oil/chips
Replacement parts
We supply the following units for this alarm — tested, warranty-backed:
- Request a quote →
A860-0360-B101
Position coder (spindle encoder) · Common cause
Need the part urgently?
Send us alarm SP9042 with your machine details — typical RFQ turnaround is 24–48h.