Typically no password by default, but check for 1234 or password .
If you are the legitimate owner of the machine and have exhausted all other avenues (checking old emails, contacting the original manufacturer, looking for sticky notes on the electrical cabinet), here are the standard steps to attempt.
We’ve all been there. You pick up a project that was programmed six years ago, the original programmer left no documentation, and suddenly you’re staring at a locked Koyo (AutomationDirect/Entivity) PLC. Whether it’s a CLICK, DL05, DL06, or a DirectLogic 205, hitting that password wall can shut down a production line.
When facing a password-locked Koyo PLC, contacting the equipment manufacturer or the official distributor is the safest, most legitimate, and often the most straightforward solution.
Keep a secure, documented record of all PLC passwords in a master project file. koyo plc password unlock
The password string can often be read in plain text or simple hex representation inside a Hex Editor tool. Note: Modern CLICK PLCs have firmware protections that prohibit this vulnerability. 3. Software & Cracking Tools: Risks to Avoid
If all else fails, contact AutomationDirect technical support for assistance with their DirectLOGIC product line.
Here are the four primary recovery methods, ranked from least invasive to most destructive.
KOYO controllers, manufactured by Koyo Electronics (now heavily integrated with AutomationDirect), use different security layers depending on the hardware generation and programming software. DirectLOGIC Series (DirectSOFT Software) Typically no password by default, but check for
: Unofficial software often floods the PLC serial port with malformed packets, forcing the CPU into a fatal error state that bricks the hardware.
Connect to the PLC using DirectSOFT or the CLICK Programming Software. Navigate to the menu. Select Clear PLC Memory or Reset to Factory Default .
Password protection is a feature that can be set by the original programmer or system integrator to safeguard their intellectual property or to prevent accidental or unauthorized modifications from plant floor personnel. It is not a defect but a designed capability meant to protect both the OEM's investment and the operational integrity of the machine.
Based on public analysis (e.g., reverse engineering by industrial security researchers): You pick up a project that was programmed
Before we begin, it's crucial to address the legal and ethical dimensions of PLC password unlocking. Attempting to bypass security measures without explicit authorization from the equipment owner or intellectual property holder is not only unethical but can also be . Unauthorized access may violate intellectual property laws, computer fraud and abuse acts, and industrial control system (ICS) security regulations. In many jurisdictions, this constitutes a criminal offense, especially if it leads to operational disruptions or safety incidents. Furthermore, in critical infrastructure sectors, legal and regulatory compliance is paramount to ensure public safety and national security.
: Require system integrators to hand over all administrative credentials, security keys, and uncompiled project files upon project sign-off.
If official channels are not an option, you might consider the following technical approaches. However, it is important to exercise caution and fully understand the risks and limitations of each.