The OBD2 protocol itself doesn’t have inherent security measures to prevent unauthorized communication with a vehicle. It’s designed for standardized communication between diagnostic tools and the vehicle’s Electronic Control Unit (ECU) for reading diagnostic data, not for overall vehicle security.

Here’s a breakdown of some key points:

• Focus on Standardization: OBD2 prioritizes establishing a universal language for diagnostic tools to interact with various car ECUs. Security wasn’t a primary concern during its inception.
• Limited Communication Scope: OBD2 communication is intended for retrieving diagnostic data like fault codes and sensor readings. It doesn’t provide access to critical systems like engine control or braking functions.
• Physical Access Needed: For OBD2 communication to occur, a physical connection between the diagnostic tool and the vehicle’s OBD port is necessary. This somewhat limits the risk of remote tampering.

However, as vehicles become increasingly reliant on computers and software, the need for automotive cybersecurity is growing. Some manufacturers are implementing additional security measures at the ECU level to prevent unauthorized access through the OBD port. These might involve:

• Password Protection: Certain ECUs may require passwords or specific key codes to establish communication.
• Encrypted Communication: Some advanced systems might encrypt communication between the diagnostic tool and the ECU to add an extra layer of security.

It’s important to note that these manufacturer-specific security measures are still under development and may not be universally adopted.

Here are some additional considerations:

• Tampering Risks: While OBD2 itself isn’t designed for security, some unscrupulous individuals might exploit it to tamper with emission control systems.
• Aftermarket Tuning: Some aftermarket performance modifications might involve using OBD2 tools to alter engine control parameters. However, this can be risky and may negatively impact performance, emissions, or even cause damage.

In conclusion, OBD2 doesn’t have built-in security features for communication. However, the industry is recognizing the growing importance of automotive cybersecurity, and some manufacturers are implementing additional security measures at the ECU level. If you’re concerned about unauthorized access to your vehicle, it’s advisable to consult your car’s manual or a qualified mechanic for specific recommendations.