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 → · Le diagnostic IA qui lit la sauvegarde de votre robot, sans rien téléverser.

ABB Error 0121Link computer fault

Error / Erreur

🇫🇷 Liaison Calculateur

GÉNÉRATION S2 / S3 — CODES HISTORIQUES (5xx & SOUS-CODES)

ABB 0121 (“Link computer fault”): Link computer fault — ABB robot hardware event on the link computer (S2/S3). Likely part: Liaison Calculateur (link computer).

Updated 2026-08-29 · LogrobotLM reference

What it means · Ce que ça veut dire

Link computer fault — ABB robot hardware event on the link computer (S2/S3). Seen across controller generations. Severity: Major. Field diagnosis below (French); your robot's own manual remains authoritative.

Erreur détectée lors des tests automatiques sur la liaison de communication série.

What to check · Que vérifier

  • Inspect the link computer, its wiring and connections first.
  • Match this code against your robot's event-log timeline before swapping parts.
  • Follow the French field checks below — they are the tested sequence for this fault.
  • Remplacez la carte du calculateur si la liaison série d'extension doit être utilisée.
  • À savoir : Similaire aux pannes de canal série 31108 sur S4.

Part to check / replace · Pièce à contrôler / remplacer

ABB 0121 points to the hardware below — start here before ordering. · 0121 met en cause l'organe ci-dessous : commencez par là.

Tap a part for every code that points to it — and verify the exact variant for your controller before ordering. · Touchez une pièce pour tous les codes qui la citent ; vérifiez la variante exacte avant commande.

Frequently asked · Questions fréquentes

What does ABB error 0121 mean?
ABB 0121 (“Link computer fault”): Link computer fault — ABB robot hardware event on the link computer (S2/S3). Seen across controller generations. Severity: Major. Field diagnosis below (French); your robot's own manual remains authoritative.
How do you troubleshoot ABB error 0121?
Inspect the link computer, its wiring and connections first. Match this code against your robot's event-log timeline before swapping parts. Follow the French field checks below — they are the tested sequence for this fault.
Which part is involved in ABB 0121?
0121 points to Liaison Calculateur (link computer). Confirm the real cause against the robot backup before replacing a part.

Related codes / Codes liés

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. · Informations indicatives issues du terrain — le manuel du constructeur et ses procédures de sécurité font foi. Ne shuntez jamais un organe de sécurité ; consignez (LOTO) avant toute intervention physique. How this reference is built →