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KUKA Error 1128 — STOP, APPROXIMATE POSITIONING IMPOSSIBLE

Error

Displayed as KSS01128 on KRC4 / KRC5 controllers

KUKA 1128 (“STOP, APPROXIMATE POSITIONING IMPOSSIBLE”): Approximate positioning impossible because of the path calculation or for timing reasons. First check: Reduce the velocity in the block and/or the acceleration until approximate positioning is possible.

Updated 2026-09-09 · LogrobotLM reference

Cause

Approximate positioning impossible because of the path calculation or for timing reasons.

Effect

Stop via braking ramp. All active commands inhibited.

Troubleshooting

Reduce the velocity in the block and/or the acceleration until approximate positioning is possible.

Related codes

1126STOP COMMAND IGNORED1125ELECTRONIC PROBE FAULT1124WRONG START POSITION1122ANALOG OUTPUTS -- DELAY REDUCTION

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 →