Hold the switch in the position for roughly 9 seconds until the STOP LED stops flashing and remains solid.
If you do not have the password and just need the PLC to be functional again for a new project, you can perform a factory reset. This will wipe the existing program, including the password. unlock s7300 plc password
Unlocking a Siemens SIMATIC S7-300 PLC depends on whether you need to the existing program or simply reset the device to factory settings for a fresh start. There is no official "legal" way to bypass a password and keep the program, as Siemens design prioritizes security. Method 1: Resetting to Factory Settings (Password Removal) Hold the switch in the position for roughly