[HOWTO-Make-a-PnP-board](HOWTO-Make-a-PnP-board) # Plug In Board Process ## Step 1 Research have wiring diagrams in random loose format: pictures, scans, PDF, text. ## Step 2 Data Entry have ECU connector pin-out in google spreadsheet form, with explicit function of each pin, often with analysis of multiple vehicles with similar pin-out. [Good example](https://docs.google.com/spreadsheets/d/1H0cZPAJFbpprgSu1Y8BiAYzXbqddvIn-Hhod4QCVQwk) ## Step 3 Breakout Breakout board for that connector to reduce risks, also a product by itself! ## Step 4 Start of KiCAD Pin-out data entry into KiCAD ## Step 5 Adapter Proteus or else adapter for specific vehicle, based on steps 2, 3 and 4. Because cheaper fabrication and less labor intense. ## Step 6 Plug In Hellen Full plug in board like Hellen if demand exists. See ## Step 7 Hellen real vehicle tests We are getting good at these Hellen boards but a board is not done until tested on a real vehicle. A master tech skill set is needed to turn a Hellen into a proven board!