ABB Error 31503 — Backup battery fault
ErrorABB 31503 (“Backup battery fault”): Voltage of both cabinet backup batteries too low. Likely part: Backup battery (Backup battery).
Updated 2026-10-22 · LogrobotLM reference
What it means
Voltage of both cabinet backup batteries too low.
What to check
- Replace both backup batteries immediately.
- Note: Similar to the loss of backup accumulators and immediate loss of robot synchronization on IRC5.
Part to check / replace
ABB 31503 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
Same hardware involved
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 →