Siemens S7-300 SF Fault

I have a problem with a PLC rack. The rack contains various DI and DO cards, AI cards, AO cards, and a AI/AO combo card. There is 1 processor and 3 IM modules. The processor is in stop and will not run. There are SF lights lit on all 4 of the AI cards, bot only those. All digital, combo, and AO cards are OK. Anyone have any quick thoughts?

A quick guess ist that a supply voltage to the analog card is missing.

If you have STEP7, go online with the PLC and investigate the diagnostics buffer.

Already looked at voltage. All power supplies running to PLC are operating normally.

As Jesper suggested, check the aux voltage on the analog modules and check the diagnostic buffer with Step 7.

i faced the same problem , after all investigations i downloaded the backup programme , it worked