MegaSquirt DB37 Connector, Grounds, and You - DIYAutoTune.com . There are a few different MegaSquirt wiring diagrams floating around the internet. For the most part, they're all the same. However some vary in regards to ground pin locations on the MegaSquirt DB37 connector. Proper grounding is one of the keys to a successful installation of any EFI system, so we want to help remove… Schematics - Megasquirt EFI . Megasquirt schematics are copyrighted and are provided for existing customers to repair or modify their ECUs. Most schematics are provided in the Hardware manual for your product. The following are additional ones that are not available within those PDFs. V2.2 board (pdf) Megasquirt 1 - V3.0 board Megasquirt-1 external wiring diagrams
