LogrobotLM

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ABB Error 39406 — Field loop overcurrent

Error

ABB 39406 (“Field loop overcurrent”): Field loop overcurrent: the field current control loop has produced a current that is too high for the indicated joint, connected to the indicated drive module. Likely part: Boucle de champ / Variateur (Boucle de champ / Variateur).

Updated 2026-10-22 · LogrobotLM reference

What it means

Field loop overcurrent: the field current control loop has produced a current that is too high for the indicated joint, connected to the indicated drive module.

What to check

  • Check the motor cable and the winding insulation of the affected axis.
  • Check the drive unit controlling the axis.
  • Only replace the drive unit after measuring on the motor side: a loop overcurrent more often comes from the load than from the electronics.
  • Note: 394xx family: the message names the joint (arg), to be noted before acknowledgement.

Part to check / replace

ABB 39406 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 →