First, ensure you have the correct ECU model. Zexel ECUs are used in several Nissan models, but the pinout can vary significantly between different models and years. 2. Consult a Repair Manual A factory repair manual or a specific ECU tuning guide for your Nissan model can be invaluable. These manuals often include detailed diagrams and pinout information. 3. Online Forums and Communities Websites like Nissan forums, Reddit, and specialized automotive tuning forums can be great resources. Enthusiasts and professionals often share pinout information, wiring diagrams, and advice. 4. ECUFLASH, OpenPort, and Other Tools If you're planning to work with tuning software, tools like ECUFLASH (for use with OpenPort 1.3 or 2.0) can provide not only pinout but also software to interface with the ECU. These tools are commonly used for Nissan ECUs, including Zexel units. 5. Consult a Professional If you're not comfortable with DIY electronics or if your project requires precise and reliable data, consider consulting with a professional automotive electrician or a tuning specialist. Sample Pinout (For Illustration Purposes) Here is a simplified example of a pinout for a generic ECU (not specific to Nissan Zexel, but for illustration):

If you're looking to modify your vehicle for performance, ensure you're also compliant with local emissions and vehicle regulations. Always refer to reliable sources and consult with professionals when in doubt.