LogrobotLM

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FANUC Alarm SYST-156 — SYSTEM Unknown hard ware

Error
Hardware
main board and memory
Controllers
R-J3iB / R-30iA
FANUC class
SYSTEM
Hardware family
FANUC teach pendant, main board, CMOS and controller battery alarms

FANUC SYST-156 (“SYSTEM Unknown hard ware”): This PCB is not used on this controller. First check: Mount the correct PCB.

Updated 2026-10-22 · LogrobotLM reference

Description

This PCB is not used on this controller.

Remedy

Mount the correct PCB.

Field diagnosis

A fitted board is not intended for this controller.

What to check

  • Fit the correct board for this cabinet.
  • Note: A spare board from another generation triggers this code at startup.

Related codes

SYST-138WARN Motherboard not installedPRIO-021SYST Unknown I/O hardwareSYST-154WARN No start in ISOLATE/BYPASS modeSYST-155ABC overrunSYST-157SYSTEM CE/RIA software does not existSYST-158PAUSE Robot cannot move in T2 mode

Indicative field information — the robot manufacturer's manual and safety procedures always prevail. Never bypass a safety device; apply lockout/tagout (LOTO) before any physical intervention. How this reference is built →