What Fanuc Control Repair Covers
Fanuc control repair deals with the CNC unit and the circuit boards in the machine’s electrical cabinet. Board repair shops work on CPU boards, axis boards, I/O modules, and control power supply units for Series 0i, 16i, 18i, 21i, 30i, 31i, and 32i controls. Operator panels and monitors on older Fanuc controls go out for board-level repair as well.
Component-level repair replaces the failed parts and returns the original board to the machine. Encoder interface faults on Fanuc boards cause a loss of position feedback and get repaired at the circuit level. Some shops follow the component repair with full functional testing on the bench.
Fanuc Control Repair Shops
CNC Electronics Inc
Charlottesville, VA
Brands: Fanuc
CNC Machine Services Inc
Snohomish, WA
Brands: Fanuc
CNC Service Group
Medina, OH
Brands: Fanuc
Flexa Systems
Lewisville, TX
Brands: Fanuc, Haas, Mazak, Okuma
Global Electronic Services
Buford, GA
Brands: Fanuc, Haas, Okuma
Machine Tool Science
Gaffney, SC
Brands: DMG Mori, Fanuc, Haas, Mazak, Okuma
T.I.E. Industrial (FanucWorld)
La Vergne, TN
Brands: Fanuc, Okuma
Tri Star CNC Services, LLC
McHenry, IL
Brands: Fanuc
Compare Fanuc Control Repair Shops
This table lists turnaround, warranty, and evaluation terms from each shop's published information.
| Shop | Repair type | Turnaround (business days) | Warranty (months) | Free evaluation | Rush service |
|---|---|---|---|---|---|
| CNC Electronics Inc | Ship-in repair | Not listed | 12 | Not listed | Not listed |
| Flexa Systems | Ship-in repair | 1-3 | 24 | Yes | Yes |
| Global Electronic Services | Ship-in repair | 3-5 | 24 | Yes | Yes |
| T.I.E. Industrial (FanucWorld) | Ship-in repair | Not listed | 12 | Not listed | Not listed |
| Tri Star CNC Services, LLC | Ship-in and on-site | Not listed | 12 | Not listed | Not listed |
Protecting Parameters and Programs
Fanuc controls keep parameters, PMC ladder logic, tool offsets, pitch error compensation data, and part programs in battery-backed SRAM. That memory needs constant battery voltage to hold the full machine setup. Parameter loss from a dead backup battery ranks as the highest-risk event for a legacy CNC control.
Fanuc controls typically back up the SRAM with a 3V lithium cell. Repair specialists recommend a new cell every three to five years and not at the first low-battery alarm. The cell change happens with the control powered on and keeps the SRAM supplied with power during the swap.
Backing Up a Fanuc Control
A complete backup of a Fanuc control goes well beyond the CNC parameter table. The backup needs CNC parameters, pitch error compensation, tool offsets, macro variables, PMC parameters, and the PMC ladder. A separate table off the standard parameter page holds the pitch error compensation data and makes that data easy to miss.
Fanuc i Series controls send the backup out to a memory card or a PC through the punch function in EDIT or MDI mode. A test read of the saved files into a second control with cleared memory confirms a usable backup. Printed copies of the parameters and a second set of backup media at another location add protection against a lost or damaged card.
Shipping a Board and Keeping Spares
Data on an SRAM chip damaged by the original failure can disappear even with battery power kept on during the repair. A parameter backup from the machine ahead of shipping protects the setup from that loss. Board repair shops strongly recommend that backup for every board sent out for repair.
Legacy Fanuc control boards went out of production years ago and now come from a secondary market with a smaller supply every year. Repair specialists suggest buying a tested and repaired spare ahead of any failure. A spare CPU board verified against the machine’s parameter backup carries less risk than an untested salvage pull.
Care for the Control Cabinet
The small brushless fans inside a legacy control can fail without setting an alarm. A dead fan shows up only through an over-temperature trip or a damaged board. Fan checks belong on the routine inspection list for the control cabinet.
Conductive contamination on legacy boards can cause erratic behavior and electrical shorts. A clean enclosure interior keeps that contamination off the boards. Older controls with CRT monitors face flyback failures on aging tubes and can move to a verified LCD conversion.