Posted 8 Oct 2021 Hi all, My system is using PLC S7-300. Now, it is being SF fault. I followed the manufacturer's sf error instructions. I replaced the CPU Module, but it is still fault. Diagnostic of Simatic announced I/O can't access for reading and writing. Please give a solution, thanks Sincerely. Share this post Link to post Share on other sites
Posted 8 Oct 2021 16 minutes ago, arrietty said: My system is using PLC S7-300. Now, it is being SF fault. I followed the manufacturer's sf error instructions. I replaced the CPU Module, but it is still fault. Diagnostic of Simatic announced I/O can't access for reading and writing. More details of the system is really required but - Is there any remote i/o (Profibus / Profinet)? Are all the i/o power supplies ok? 1 person likes this Share this post Link to post Share on other sites
Posted 8 Oct 2021 Just an SF light or SF and BUS Fault light? 1 person likes this Share this post Link to post Share on other sites
Posted 8 Oct 2021 (edited) Only SF light and all power oke. Edited 8 Oct 2021 by arrietty Share this post Link to post Share on other sites