What vehicle manufacturer protocols are supported by Innova OBD2 scan tools?

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Vehicle manufacturers utilize various protocols for communication and control within vehicles. A Protocol is a set of rules and procedures for regulating data transmission between computers, and between testing equipment and computers. Different types of protocols (ISO 9141, Keyword 2000, J1850 PWM, J1850 VPW, LIN, and CAN) are in use by vehicle manufacturers. Here are the different types of protocols commonly employed in the automotive industry:

• Controller Area Network (CAN): CAN is the most widely used protocol in modern vehicles. It provides a standardized communication bus that allows various electronic control units (ECUs) to exchange data. CAN enables real-time transmission of messages between different systems, such as the engine control unit, braking system, and infotainment system.
• Local Interconnect Network (LIN): LIN is a lower-cost, slower-speed protocol designed for communication between different subsystems within a vehicle. It is often used for less critical tasks, such as controlling interior lighting, mirrors, or window motors. LIN offers a simplified and cost-effective alternative to CAN.
• Keyword 2000 (KWP2000): KWP2000 uses a design, where the diagnostic tool sends requests to the ECU to obtain information or perform specific actions. The communication occurs over a serial connection, such as a physical wire or an ISO 9141-2 or ISO 14230-4 compliant interface. KWP2000 allows diagnostic tools to communicate with the ECUs in a vehicle to retrieve diagnostic trouble codes (DTCs), monitor live data, and perform various diagnostic functions. It enables technicians to diagnose and troubleshoot issues with the vehicle's systems and subsystems.
• ISO 9141: The ISO 9141 protocol is a communication protocol used in the automotive industry for diagnostics and communication between electronic control units (ECUs) in vehicles. It's part of the International Organization for Standardization (ISO) standards and is commonly referred to as ISO 9141-2. ISO 9141-2 specifies two variants of the protocol: ISO 9141-2 L-LINE and ISO 9141-2 K-LINE. The K-LINE variant uses a single bidirectional data line, while the L-LINE variant employs a single-wire communication bus. Both variants support a data rate of 10.4 kilobits per second (Kbps).
• J1850 PWM (Pulse Width Modulation): The J1850 PWM protocol defines the electrical and physical specifications for communication between electronic control units (ECUs) in a vehicle. It specifies the voltage levels, timing, and message formats used for communication over a two-wire serial data bus. In J1850 PWM, data is transmitted by varying the pulse width of the signal. A shorter pulse width represents a logical 1, while a longer pulse width represents a logical 0. The protocol uses a bit rate of 41.6 kilobits per second (Kbps).
• J1850 VPW (Variable Pulse Width): The J1850 VPW protocol uses a single-wire communication bus, where data is transmitted through voltage pulses of varying widths. It operates at a baud rate of 10.4 kbps (kilobits per second) and is typically used for low-speed applications within the vehicle, such as engine diagnostics, transmission control, and some body control functions. In the J1850 VPW protocol, a series of voltage pulses represents binary data. A logic 0 is represented by a longer pulse width, while a logic 1 is represented by a shorter pulse width. The data transmission occurs between a master device, typically a diagnostic tool, and slave devices, which are the ECUs in the vehicle.

Connector design and location is dictated by an industry wide (OBD2) standard. Vehicle manufacturers can use the empty DLC terminals for whatever they would like. However, the DLC of every vehicle is required to provide pins 4 and 5 and 16 as defined below. Further, after the CAN protocol was fully implemented in the 2008 model year, all vehicles must use pins 6 and 14 as defined below:

• Terminal 2 – SAE J1850 10.4 kbits/s (kbps) variable pulse width serial data (GM Class2) or SAE J1850 41.6 kbps pulse width modulation serial data high line (Ford)
• Terminal 4 – Scan tool chassis ground
• Terminal 5 – Common signal ground for serial data lines (Logic Low)
• Terminal 6 – ISO 11898/15765/SAE J2284 CAN serial data high line
• Terminal 7 – ISO 9141 K serial data line or ISO 14230 (Keyword 2000) serial data line (DaimlerChrysler/Honda/Toyota)
• Terminal 10 – SAE J1850 41.6 kbps pulse width modulation serial data low line (Ford)
• Terminal 14 – ISO 11898/15765/SAE J2284 CAN serial data low line
• Terminal 15 – ISO 9141 L serial data line or ISO 14230 (Keyword 2000) serial data line (DaimlerChrysler/Honda)
• Terminal 16 – Scan tool power (unswitched battery positive voltage)

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