910

Navigate to SYSTEM > CURRENT screen and check battery voltage display. Voltage should read 3.0VDC or higher. If below 2.9VDC, battery replacement is required immediately.

Power down the CNC completely. Replace the backup battery on the main CPU board (typically located near the CF card slot or under the front panel). Use only FANUC-approved batteries to prevent voltage mismatch.

Before removing old battery, ensure full parameter and program backup is available. SRAM will be lost within 5 minutes of battery removal.

After battery replacement, power on the control. Clear all parameters by setting parameter 0 (Param Write Enable) to 1, then execute emergency clear (hold RESET + DELETE keys simultaneously during power-on on some models, or use SYSTEM > CLEAR menu on 0i-F/31i/32i).

Emergency clear will erase ALL parameters, offsets, programs, and macro variables. Ensure backup data is ready for reload.

Reload all parameters from backup via RS-232, CF card, or USB memory. Reload PMC ladder, tool offsets, work offsets, and part programs. Verify parameter 0 is set back to 0 (write protect) after reload. Cycle power and confirm alarm 910 does not return.

Verify battery voltage at SYSTEM > CURRENT screen is above 3.0VDC. If voltage is good but alarm persists after power cycle, SRAM hardware failure is likely.

Attempt SRAM clear by accessing SYSTEM > MAINTENANCE screen (password may be required on 30i/31i/32i). Execute 'ALL CLEAR CNC' function. If alarm 910 reappears immediately or after power cycle, SRAM chip or board is defective.

ALL CLEAR will erase all CNC data. Have complete backup ready before executing.

Replace the main CPU board (part numbers vary: A20B-8200-0540 for 0i-MD, A20B-8100-0880 for 31i-B, etc.). Install new board, load system software from CF card if required for 0i/30i/31i/32i series, then reload all CNC data from backup.

Ensure replacement board matches exact model and software version. Incompatible boards will cause boot failures.

After board replacement and data reload, perform full diagnostic check at DIAGNOSIS > PARAMETER screen to verify SRAM integrity. Monitor for 24-48 hours to confirm alarm 910 does not recur.

Check for recent power outages, brownouts, or electrical work in facility. Review CNC operation log at ALARM > HISTORY screen to identify if alarm 910 occurred during power fluctuation or parameter write operation.

Inspect incoming AC power quality. Measure line voltage at control transformer input terminals (should be stable within ±10% of rated voltage). Check for proper grounding at PE terminal and verify no shared neutral with high-load equipment like welders.

Use proper lockout/tagout procedures before inspecting electrical connections.

Clear SRAM by accessing SYSTEM > CLEAR menu or executing emergency clear procedure. Reload all parameters and data from known good backup. Set parameter 0 back to 0 after reload and cycle power to verify alarm clears.

Emergency clear erases all CNC data including parameters, programs, and offsets.