| Step | Action | |------|--------| | 1 | Power off the CPU. | | 2 | Insert a blank MicroSD card containing only a file named s7_clearpsw.s7s (created via a hex editor: ASCII string CLR_PSW followed by 0x00). | | 3 | Set the CPU switch to . | | 4 | Power on the CPU. Wait for STOP LED to flash 3 times (indicates password reset). | | 5 | Power off, remove the SD card. | | 6 | Power on. Connect MicroWIN SMART → no password prompt. |
The Siemens SiePortal provides instructions on creating a reset card that, when inserted into a powered-off PLC and then powered on, will wipe the internal memory and password. Recovery Alternatives siemens s7 200 smart password unlock fixed
Operational Considerations