SRVO-069

Pulsecoder Serial Data CRC Error

Fanuc · R-30iB Mate + Mate Plus Robot

What does SRVO-069 mean?

The serial data transmitted from the Pulsecoder was disturbed during communication, resulting in a Cyclic Redundancy Check (CRC) error. This indicates data corruption, which can be caused by electrical noise, poor shielding, or faulty communication components.

Common Causes

  • Corrupted data packets transmitted over the pulsecoder serial interface.
  • Faulty pulsecoder generating incorrect checksum values.
  • Noise or interference corrupting the cyclic redundancy check (CRC) bits.
  • Loose or damaged serial communication cables (e.g., P1-31, P1-32).
  • Servo controller not correctly interpreting CRC data from the pulsecoder.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Ensure the robot connection cable (RMP1, RP1) connector (CRF8) on the 6-Axis servo amplifier and the connector on the motor side are tightly connected.

  2. 2

    Check that the shielding of the robot connection cable (RMP1, RP1) is securely grounded in the cabinet.

  3. 3

    Replace the Pulsecoder.

  4. 4

    Replace the servo amplifier.

  5. 5

    Replace the robot connection cable (RMP1, RP1, RM1).

  6. 6

    Replace the internal cable of the robot (for the Pulsecoder, or for the Motor).

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Verified technical data. Last updated: March 2026

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Source: Fanuc R-30iB Mate + Mate Plus Robot