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
Remove the unpartnered controller and troubleshoot the cause of the switchover.
- 2
Add a partner controller to the secondary chassis.
- 3
Troubleshoot the cause of the switchover, and synchronize the system.
Verified technical data. Last updated: March 2026
Related Faults
Source: Logix 5000