4

Flash Memory Write Error

Wago · PFC200 PLC

What does 4 mean?

An error occurred during an attempt to write data to the controller's flash memory. This can lead to corrupted configuration or program data and indicates a critical issue with the flash memory hardware or its write operations. This is a severe internal controller fault.

Common Causes

  • Defective flash memory hardware within the controller
  • Interrupted or failed write operation to flash memory due to an internal fault
  • Controller internal fault during memory access causing write failures

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Switch off the power to the controller.

  2. 2

    Replace the controller.

  3. 3

    Switch the power back on after replacement.

Browse all codes in this manual (23)
Verified technical data. Last updated: March 2026

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