What causes fault code AB-F009 (CompactLogix Nonvolatile Memory Fail)?

Flash memory chip reaching end of write-cycle life. Power interruption during program save/download. Static discharge damaged memory chip. Firmware update interrupted. Manufacturing defect

How do I fix fault code AB-F009?

Download a known-good backup of the program to the processor. If download fails, attempt firmware flash recovery. Contact Rockwell tech support for RMA if memory is physically failed. Ensure UPS protects PLC during firmware updates and program saves. Replace processor if memory recovery is not possible

CompactLogix Nonvolatile Memory Fail

AB-F009

CompactLogix processor detected a failure in nonvolatile (flash) memory. Program storage may be compromised.

critical allen-bradley

allen-bradley compactlogix memory flash firmware

Probable Causes (ranked)

Flash memory chip reaching end of write-cycle life
Power interruption during program save/download
Static discharge damaged memory chip
Firmware update interrupted
Manufacturing defect

Fix Steps

1 Download a known-good backup of the program to the processor
2 If download fails, attempt firmware flash recovery
3 Contact Rockwell tech support for RMA if memory is physically failed
4 Ensure UPS protects PLC during firmware updates and program saves
5 Replace processor if memory recovery is not possible

Field Trick

If you can get online but can't download, try a firmware downgrade then re-upgrade. Sometimes this resets the flash controller.

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