In early S7-1200 firmwares (pre-V3.0), Siemens used a weak hashing algorithm for the online access password.
Do you have an official on hand?
The only official and secure method to regain control of the hardware is to wipe the internal load memory. This comprehensive guide provides step-by-step instructions on the top methodologies to safely unlock your S7-1200 CPU The Reality of S7-1200 Protection Levels Siemens S7-1200 controllers Go to product viewer dialog for this item.
In TIA Portal, open the project tree, navigate to "Card Reader/USB memory," find your card, and delete any existing files. Create an Empty Transfer Card: Right-click the empty memory card in TIA Portal. Select Operation > Card type and set it to Transfer . Power Down: Turn off the power supply to the S7-1200 CPU. s71200 password unlock top
Siemens S7-1200 controllers utilize secure hardware modules and block-level encryption to safeguard intellectual property and industrial operations.
: Older hardware like the S7-300 relied on default passwords (e.g., "Basisk"), but modern S7-1200 hardware completely lacks master unlock codes or default engineering backdoors.
Crucially, the standard "Reset to factory settings" function accessible through TIA Portal cannot delete the password when the password is unknown. Siemens explicitly confirms that "if you forget the password of S7-1200 that was set before and the program and password inside S7-1200 cannot be deleted through 'Reset to factory defaults', memory card will become the only way to delete them". In early S7-1200 firmwares (pre-V3
requires performing a complete factory reset using an official if you have lost the password hash. Because Siemens hardware relies on secure one-way cryptographic hashes rather than plain-text passwords, there is no master backdoor code or bypass utility that can extract a forgotten password without wiping the internal load memory.
An external SD card reader connected to a PC running TIA Portal. Step-by-Step Reset Procedure
Once the lights stop flashing (usually a solid STOP light), turn off the power, remove the card, and turn the power back on. Select Operation > Card type and set it to Transfer
Ensure the card is empty by deleting all visible files (do not delete hidden files). Execute the Reset Power off the PLC. Insert the empty transfer card. Power on the PLC. Wait for the LED to flash.
For a brand new SIMATIC card, it may already be pre-formatted correctly. However, confirm its status before proceeding.
: Before resetting a locked PLC that contains valuable custom code, consider whether alternative solutions (such as contacting the original programmer, reverse engineering the machine's operation, or replacing the control system entirely) might be more appropriate.
: You cannot extract the project from the CPU memory.
Siemens S7-1200 Go to product viewer dialog for this item. Password Unlock: The Top Methods and Best Practices In industrial automation, Siemens S7-1200 Programmable Logic Controllers (PLCs) Go to product viewer dialog for this item.
