Emergency error codes, PLC alarms, and the parts behind them, for legacy Fadal VMCs running the CNC88, CNC88HS, 88MP, or FANUC 0i-MC control. Built from OEM documentation and real technician-reported failures, organized so you can go from fault number to the part that actually fixes it.
Which Control Do You Have?▼
CNC88 / CNC88HS / 88MP
The original Fadal-proprietary control, used on most Chatsworth-built machines through the mid-2000s. Uses numbered Emergency Error Codes (1 to 33) and descriptive text error messages.
FANUC 0i-MC (FX Series)
Later Fadal machines built on a FANUC control platform. Uses a separate Fadal-written PLC alarm and message layer, different numbering from CNC88. Don't cross-reference between the two systems.
Emergency Error Codes: CNC88 / 88HS (1-33)▼
Diagnostic priority order when multiple faults hit at once: PLC, then servo drive, then spindle drive, then lube, then E-STOP. A higher-priority message can mask a lower one underneath it.
| # | Description | Likely Cause / Part |
|---|---|---|
| 1 | No motor feedback | Resolver/encoder, feedback cable, 1010 card |
| 2 | Encoder not responding properly | Spindle encoder (rigid tap) |
| 3 | Logic jumper incorrect / command signal missing / motor-tach connection | J4 slot jumpers, motor/tach wiring, 1010 card |
| 4 | Encoder is not 1024 line | Wrong or failed encoder |
| 5 | No index mark detected | Encoder/scale index, cold start |
| 6 | Switch 1 disabled | Not used |
| 7 | Rigid tap precycle encoder count problem, not enough count | Spindle feedback / encoder |
| 8 | Spindle magnet not detected / spindle not turning | Hall sensor, magnet, command signal |
| 9 | Spindle fault line down | Spindle inverter/drive |
| 10 | Encoder and magnet not responding / spindle not turning | Spindle drive and feedback |
| 11 | Following error cannot be scaled for command signal | Servo tuning, 1010 card |
| 12 | Motor overload, step command checksum error | 1010 card to CPU communication |
| 13 | Motor overload, following error greater than overload factor | Binding, amp, motor, gib |
| 14 | Move transfer fault, buffer indicator not set | 1010/1030 card |
| 15 | Time out, rigid tap precycle test | Spindle feedback/magnet |
| 16 | Time out, resolver response | Resolver, 1010-4 card |
| 17 | Bad reading on resolver port | Resolver, resolver cable, 1010-4 card (or motor vibration) |
| 18 | Amplifier fault line down | Axis amplifier |
| 19 | Stack overflow, overloaded with step command | 1010 card |
| 20 | Move transfer fault, move setup incomplete | 1010/1030 checksum |
| 21 | Unexpected interrupt | 1010-4, 1030, or main CPU |
| 22 | Bad scale reading | EXE box, glass scales, cables, 1010-4 |
| 23 | Motor overload during stand-by | See code 13 |
| 24 | Motor overload during rapid | See code 13 |
| 25 | Motor overload during contouring | See code 13 |
| 26 | Motor overload during jog | See code 13 |
| 27 | Time out on return to magnet | Spindle magnet/orientation, rigid tap |
| 28 | Time out, not detecting last magnet, no calibration | Spindle magnet/Hall sensor |
| 29 | Rigid tap precycle encoder count, too many counts | Spindle feedback, see code 7 |
| 30 | Survey table cleared due to bad survey | Checksum/survey, 1010 card |
| 31 | Time out on orientation | Spindle orient, Hall sensor/magnet (shows as "C axis fault") |
| 32 | Spindle will not stop, check inverter zero speed | Spindle inverter/drive |
| 33 | Encoder channels are reversed, rigid tap | Encoder wiring at spindle card |
On Fadals the spindle is addressed as the "C axis." A "C axis fault" on screen carries these spindle-related numbers, most often when trying to turn the spindle (code 10) or during a tool-change orient (code 31).
FANUC 0i-MC PLC Alarms (FX Series)▼
| # | Category | Description / Fix |
|---|---|---|
| 1002 | Door/Safety | Dual door switch failure |
| 1103 | ATC | ATC can't extend during spindle operation |
| 1110/1111 | ATC | Carousel extend/retract failed |
| 1113 | ATC | ATC slide sensors are bad |
| 1114 | ATC | ATC slide stop in wrong place / time out |
| 1117 | ATC | Slide can't retract because drawbar is open |
| 1125 | ATC / Drawbar | Draw bar time out, check draw bar sensor |
| 1130/1132 | Axis/Brake | 4th/5th axis brake on |
| 2020 | Lube | Low lube, refill Vactra-2 |
| 2026-2037 | Lube | Air-oil pressure faults |
| 2044/2045 | ATC | Tool-arm / magazine overload trip |
| 2060-2087 | ATC | Per-step tool-change position/sensor faults. 2064/2066 are drawbar clamp/release. |
| 2130 | Coolant | Low coolant / pump failure |
| 2131/2133 | Axis/Brake | Use M61/M62 to release brake |
| 2136/2137 | Spindle/Gear | Possible PCB-0321 failure or broken spindle belt |
| 2222 | I/O | I/O output overcurrent |
This is not the complete FANUC PLC alarm range, it covers the categories most commonly reported by technicians. Contact us if you have a code not listed here.
Common Failure Patterns▼
Spindle drive faults (codes 9, 32)
The original Mitsubishi FreqRol Z300 inverter is the classic failure point. Intermittent motor-overload faults, speed pulsing on cold starts, or failure to stop at high RPM usually trace here. The Calmotion CALAMP series is the standard drop-in replacement.
Resolver / encoder faults (codes 1, 16, 17)
Cascading faults across random axes are often a power supply problem masquerading as a resolver problem, check power first. If the resolver itself is bad, coil-pair resistance should read roughly 35-45Ω and 125-135Ω on AMCI units, or 70-80Ω and 190-220Ω on Harowe units. See How to Test a Resolver for the full procedure.
1010 axis card faults
Swap the suspect card into a different slot. If the fault follows the card, the card is bad. If the fault stays with the slot, the problem is the 1060 backplane or cabling. The J4 jumper IC must stay with the slot, not the card, or you'll get axis runaway.
Power supply issues
Random multi-axis faults, failure to start, or scrolling E-stop errors often trace to the ±12V/+5V DC supply rather than any single axis. Check power before replacing resolvers or cards.
ATC / turret faults
Turret rotating one direction only, or "ATC Turret Failure," usually traces to the turret encoder/motor, broken wires in the flex conduit, a dislodged power-supply capacitor, or the servo-turret amplifier.
Drawbar faults (PLC 1117, 1125)
Tool won't release or won't retain, check air pressure (80-90 PSI, 120 PSI tool-out regulator) before assuming the drawbar sensor or Belleville spring stack has failed.
Orientation faults (codes 8, 28, 31)
Usually just a sensor gap issue, not a failed part. Loosen the Hall-effect orientation sensor, let the gap close slightly against the spindle pulley magnet, and retighten.
Shop the Fix▼
Know Your Part?
Shop spindle drives, encoders and resolvers, drawbar components, ATC parts, or all Fadal parts. Can't identify the part from your fault code? Email support@thecncsource.com with your machine model and the fault number.
Need the Full Procedure?
Identified your issue? See Fadal How-To Guides for step-by-step diagnostic procedures with tested values, starting with resolver testing.