12-33

Unpartnered controller in primary chassis

Allen-Bradley · Logix 5000

What does 12-33 mean?

An unpartnered controller was identified in the new primary chassis following a switchover event. This indicates a configuration mismatch in the redundant system.

Common Causes

  • Unpartnered controller identified in the new primary chassis after a switchover

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Remove the unpartnered controller and troubleshoot the cause of the switchover.

  2. 2

    Add a partner controller to the secondary chassis.

  3. 3

    Troubleshoot the cause of the switchover, and synchronize the system.

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

Related Faults