HAAS® Alarm 201 — PARAMETER CRC ERROR
Part of: our HAAS® alarm reference · covering 60 of the most common alarms.
What it means
The integrity check on the machine parameters failed. The control thinks one or more stored parameters has been corrupted.
Common causes
- Backup battery low and parameters drifted (often paired with 124)
- Bad shutdown during parameter write
- Memory hardware fault
What to check first
- Don't power off until backed up — you may lose parameters
- Service call: parameters need to be reloaded from a known-good backup
Prevention
Communications and parameter-integrity faults are rarely caused by anything the operator did. They're typically end-of-life components or the result of a bad shutdown. The single most useful preventative step is to replace the control's backup battery on schedule (every 3-5 years) and to ensure parameter and offset backups are taken regularly.
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.