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ABB Error 39478 — Robot electric motor fault

Error

ABB 39478 (“Robot electric motor fault”): Excessive temperature measured via the PTC sensor of a robot axis motor (overload). Likely part: Moteur électrique robot (Moteur électrique robot).

Updated 2026-10-22 · LogrobotLM reference

What it means

Excessive temperature measured via the PTC sensor of a robot axis motor (overload).

What to check

  • Check that there is no obstacle or robot axis collision.
  • Allow the robot to cool down.
  • Note: Similar to motor overheating on older cabinets.

Part to check / replace

ABB 39478 points to the hardware below — start here before ordering.

Tap a part for every code that points to it — and verify the exact variant for your controller before ordering.

Related codes

32540Drive unit / firmware fault32541Drive unit / firmware fault39008Drive units fault

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 →