Code ER96: IO Link MAX GROUP
Issue Description & Safety Warning
The Fanuc 30i/31i/32i CNC has triggered a critical IO Link MAX GROUP alarm. Immediate attention from a qualified operator or maintenance technician is required to prevent secondary damage to the equipment or spoiled parts during the manufacturing cycle. Always ensure standard safety and LOTO procedures are followed before accessing electrical cabinets.
Official Troubleshooting Steps
OVER(CHn) (Note 3) (1) Check the PMC paths and addresses of blocks 1 and 2 in channel n in the CONFIG PARAM screen. (2) Check the total number of groups in blocks 1 and 2 in I/O module allocation setting. (3) Check the parameter setting for the Selectable I/O Link assignment function. When 2-path allocation for the I/O Link channel is used, the total number of groups in blocks 1 and 2 exceeds 16. All I/O devices connected to the channel for which this alarm was issued are not linked. The ladder program is run even when this alarm is issued.
Source: Fanuc Series 30i/31i/32i-A Maintenance Manual, Appendix A Alarm List — PMC alarms (B-64485EN/01)
Last reviewed: 2026-07-01 · Verified against the manufacturer’s official documentation.
About Fanuc 30i/31i/32i CNC Alarms
Fanuc controllers include extensive self-diagnostics that flag or halt the machine when a fault is detected. Error code ER96 on the 30i/31i/32i CNC identifies one specific fault condition — its documented cause and the official corrective steps are listed above, sourced from Fanuc's service documentation. Always confirm against the manual for your exact machine configuration and follow LOTO procedures before servicing.
Complete Alarm List: 85 Fanuc 30i/31i/32i CNC codes.
Have a better solution?
Help the industrial community by sharing your repair experience for code ER96.
Need a searchable reference for more Fanuc 30i/31i/32i CNC manuals?
We structure equipment manuals into searchable code, title, cause, solution, safety note, and source-reference data. Send a PDF and example searched codes when you need public pages, private search, or structured exports.
Space reserved for Google AdSense / Industrial Affiliate Links
Monetization target for 2026