LogrobotLM

LogrobotLM — AI fault diagnosis for ABB · KUKA · FANUC robots. It reads your robot backup in your browser (never uploaded) and pinpoints the fault. Try it free →

FANUC Alarm PALT-121 — WARN Could not read …

Manufacturer wording — WARN Could not read %s
The manual prints placeholders; your controller fills them in with the real group, axis or number.

FANUC PALT-121 (“WARN Could not read …”): Could not read the unitload.dt file - Data error. First check: Check the motet communication and PTPC status.

Updated 2026-09-17 · LogrobotLM reference

Description

Could not read the unitload.dt file - Data error.

Remedy

Check the motet communication and PTPC status.

Related codes

PALT-118WARN Cannot use MODIFYPALT-119WARN Stn file not loaded or createdPALT-122WARN Cannot go to DETAIL pagePALT-123WARN Data modification disallowed

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 →