ControlLogix Major Fault Type 7 Code 40 (Store Failed): Fix

Q: What causes Rockwell Automation / Allen-Bradley ControlLogix / CompactLogix (Logix 5000) fault T07:C40?

1. Memory card locked (1756-L7x): Check the card’s lock switch. 2. Memory card failed or worn: Retry once; if it fails again, replace the card with a Rockwell-approved one.

Storing the project to nonvolatile memory failed. Rockwell’s corrective action: try the store again; if it fails again, replace the memory card. On 1756-L7x controllers, verify the memory card is unlocked.

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When it happens

During a store of the project to the memory card
After a download with store-to-nonvolatile-memory selected

Likely causes and checks

1Memory card locked (1756-L7x)

Points to it: Store fails immediately on an L7x controller.
Check: Check the card’s lock switch.

2Memory card failed or worn

Points to it: Store fails repeatedly; the card is old or from another system.
Check: Retry once; if it fails again, replace the card with a Rockwell-approved one.

Telling it apart

C40 is a failed store; C41, C42 and C43 are failed loads (type mismatch, revision mismatch, bad checksum).

Evidence to collect

Major Faults tab screenshot
Controller catalog number and memory card type
Memory card lock state

Work on fuel trains, burners, pressure vessels and electrical equipment must be done by qualified personnel following the manufacturer’s documentation and local codes. Never bypass a safety device or interlock.

Rockwell Automation / Allen-Bradley ControlLogix / CompactLogix (Logix 5000) fault T07:C40: Nonvolatile fault: store to nonvolatile memory failed