Development of a Diagnostic Tool to Communicate via Several Protocols using J2534 Pass-Thru APIs

About the Customer

Our customer is a tier-1 supplier of automotive solutions.

Business Challenge

The idea to develop a diagnostic tool that could switch between different communication protocol came with several challenges for the customer. First, they required the application layer that constituted vehicle diagnostic protocols such as OBD, KWP 2000, UDS etc. In addition to the upper layer, a pass-thru protocol was a must in order to switch between them.

Our customer understood the use of J2534 as the ideal choice for a pass-thru; however, they needed a technology partner who could integrate all these components together in the vehicle ECU. The diagnostic solution was also to be designed as a future-ready solution where more ECU diagnostics protocols could be added without worrying about the underlying communication medium. In short, the customer required a scalable vehicle diagnostics solution.

Embitel’s Solution

Having developed a somewhat similar solution for one our customers, we understood the challenges very clearly. Our automotive team was able to grasp the exact pain-points of the customer and provide a targeted solution. When the customer learnt about our library of re-usable vehicle diagnostics and ECU communication stacks, they knew we were the right choice for the project.

• We conceived a diagnostic solution that enables the diagnostic protocol such as OBD, KWP 200 etc. to switch between the communication protocol viz. CAN, LIN, KLINE & others. For instance, the diagnostic tool can communicate via CAN in one vehicle and LIN in another. Even if the same vehicle has more than one communication medium, it can switch between them.
• As per the requirement of the customer, the solution was designed in a way to establish communication through different protocols simultaneously.
• We utilized J2534 pass-thru protocol to achieve this switching mechanism.

Post multiple discussions and brain-storming sessions with the customer, we were able to identify the deliverables. Following modules were then developed as per the requirements:

Communication Protocols: Communication protocols including ISO 15765 and TP 2.0 over CAN, Kline over UART were developed, configured, and integrated to the solution.

J2534 based Pass-Thru protocol: J2534 APIs were developed and integrated. These APIs would handle the switching mechanism. As a pass-thru protocol, these will also handle the transport of data packets from ECU to diagnostic device.

Application Layer: We developed and integrated diagnostic protocols as per the customer’s requirements. The protocols OBDII (ISO 15031), UDS (14229), KWP 2000 (ISO 14230) were developed as the top layer (Application Layer).

While developing these components, our team mapped each communication protocol to its physical channel, viz. Channel 0 to High-speed CAN, Channel 1 to fault-tolerant channel, Channel 2 for normal CAN and so on.
 

Embitel Impact

With our technology assistance, our customer was able to develop a diagnostic solution that could be used for multiple communication protocols. The diagnostic protocols in the application layer are agnostic of the underlying communication medium as J2534 handles the transport of data. This enables the customer to add additional components in the applications without worrying about the low-level modules.

We were also able to reduce the turn-around time by 8-10 weeks by deploying ready-to-integrate protocol stacks such as OBD, UDS, KWP 2000, CAN, LIN, Kline etc. Our team could also deliver J2534 pass-thru protocol in the least possible time as we already had the experience of deploying a similar solution for our previous customers.
 

Tools and Technologies

• OBD tool for Kline testing
• PCan and CANoe for CAN testing