HAAS® Alarm 109 — Y SERVO OVERLOAD
Part of: our HAAS® alarm reference · covering 60 of the most common alarms.
What it means
Same as 108 but on Y. Motor is overloaded — drawing too much current.
Common causes
- Aggressive cuts pushing Y harder than it can handle
- Mechanical binding under the table
- Failing servo amplifier or motor
- Way lube failure causing increased friction
What to check first
- Reduce cutting load and back out safely
- Check way lube delivery to Y
- Look for chip build-up that could be loading the axis
Prevention
Use constant-engagement toolpaths (adaptive or trochoidal) for roughing rather than full-width slotting. Don't ignore early warning signs like rising spindle load over a production run — that's usually a worn cutter loading the axes harder than it should. Keep way covers clean and the lube system topped up.
If you’re still stuck
If you’ve worked through the checks above and the alarm hasn’t cleared — or if it cleared and came back — that’s the point to call. Persistent alarms after a reset usually mean a real component fault, and pushing through them risks turning a simple repair into a bigger one. Keith covers HAAS® breakdowns across the UK with same-day phone diagnosis.
A note on this guide. Alarm wording and numbering can vary by HAAS® machine model and software revision. The descriptions here are written in plain English to help you understand what the machine is reporting and what to check first — they’re not a substitute for the official HAAS® operator manual or for a qualified service engineer’s diagnosis. Always confirm the exact alarm message on your screen and consult your machine’s documentation before attempting any repair.