EL
ErrorLib
Brands
||
  1. Home
  2. Allen-Bradley
  3. MicroLogix 1400 Programmable Controllers
  4. ERR_INVALID_PACKET_CRC
About·Privacy·Terms

ErrorLib — Industrial Fault Code Library

Disclaimer: ErrorLib is an independent technical reference tool. While we aim for accuracy, always verify with the manufacturer’s official service manuals before performing maintenance on industrial equipment. ErrorLib is not affiliated with the brands listed.

ERR_INVALID_PACKET_CRC

Received packet has invalid CRC

Allen-Bradley · MicroLogix 1400 Programmable Controllers

What does ERR_INVALID_PACKET_CRC mean?

A received Modbus TCP packet contained an invalid Cyclic Redundancy Check (CRC) in its data portion. This indicates data corruption during transmission or an improperly formed packet from the sender.

Common Causes

  • Network interference or noise corrupting data during transmission.
  • Faulty network hardware (cables, switches, network interface card).
  • Remote Modbus TCP client sending malformed packets due to software or configuration error.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check the integrity of network cabling and connections between the controller and the remote device.

  2. 2

    Verify the remote Modbus TCP client is sending correctly formatted Modbus TCP packets.

  3. 3

    Inspect network hardware for faults and ensure proper grounding.

  4. 4

    Monitor network traffic with a protocol analyzer to identify the source of corruption.

Browse all codes in this manual (60)
Verified technical data. Last updated: April 2026

Related Faults

-1Output Error-2Overlap Error-3Undefined Accel/Decel
Source: Allen-Bradley MicroLogix 1400 Programmable Controllers
Open Manual (Page 330)Search more codes in this manual