While Firewire (IEEE 1394) was a popular high-speed data transfer protocol used in various applications, including audio and video editing, it cannot be used to access OBD2 computers in vehicles.
OBD2 (On-Board Diagnostics II) systems utilize specific communication protocols for accessing diagnostic data. These protocols include:
- SAE J1850 VPW (Variable Pulse Width): Primarily used in Ford vehicles.
- SAE J1850 PWM (Pulse Width Modulation): Primarily used in General Motors vehicles.
- ISO 9141-2: Commonly found in European and Asian vehicles.
- ISO 14230-4 KWP2000 (Keyword Protocol 2000): A more advanced protocol used in various vehicles.
- ISO 15765-4 CAN (Controller Area Network): The most common protocol in modern vehicles.
Firewire is not compatible with any of these OBD2 protocols. It operates on a different physical layer and uses a different communication standard. Attempting to connect a Firewire device to an OBD2 port would not work and could potentially damage the vehicle’s diagnostic system.
Why CAN is the Dominant OBD2 Protocol:
CAN (Controller Area Network) has become the predominant protocol for OBD2 communication due to its robustness, speed, and ability to handle large amounts of data. It allows various electronic control units (ECUs) within the vehicle to communicate with each other efficiently. This enables comprehensive diagnostics and real-time monitoring of vehicle performance.
Accessing OBD2 Data:
To access OBD2 data, you need a dedicated OBD2 scanner or code reader. These devices use the appropriate communication protocols to connect to the vehicle’s OBD2 port and retrieve diagnostic information. They typically connect via a physical cable or wirelessly using Bluetooth or Wi-Fi.
Modern OBD2 scanners offer a wide range of functionalities, from reading and clearing diagnostic trouble codes (DTCs) to displaying live sensor data and performing advanced diagnostics. Choosing the right scanner depends on your specific needs and the type of vehicle you are working on.
Conclusion:
Firewire is not compatible with OBD2 systems. To access OBD2 data, you need a dedicated OBD2 scanner that supports the correct communication protocols. CAN is the most common protocol used in modern vehicles, offering fast and reliable data transfer for comprehensive diagnostics. Using the correct tools and understanding the underlying communication protocols are essential for effective vehicle diagnostics and repair.
