MS2/V3.57 Hardware Manual Megasquirt-2 Product Range MS2/Extra 3.4.x Dated: 2016-02-02 Hardware manual covering specific wiring and configuration of your Megaquirt MS2/V357 ECU. This version of the documentation applies to: • MS2 on a V3.57 mainboard as shown above running firmware MS2/Extra 3.4.x (See the Setting Up manual for more detail on version numbers.) Does not apply to other Megasquirt products or other firmware versions. (c) 2014-6 James Murray MS2V3.57 Hardware Guide (MS2/Extra 3.4.x) Table of Chapters 1 Introduction..............................................................................................................................7 2 Megasquirt System Hardware.................................................................................................9 3 Wiring.....................................................................................................................................11 4 Fuel System...........................................................................................................................45 5 Ignition System - fundamentals.............................................................................................57 6 Ignition system - specific operating modes...........................................................................97 7 Throttles...............................................................................................................................161 8 Optional Hardware..............................................................................................................162 9 Example wiring....................................................................................................................162 10 Further information............................................................................................................164 11 Appendix A Schematics.....................................................................................................164 12 Appendix B: junkyard guide to finding EDIS.....................................................................178 13 Appendix C: V3.57 Board Setup / Jumpers......................................................................183 14 Revision history.................................................................................................................186 (c) 2014-6 James Murray 2016-02-02 Page 2/186 MS2V3.57 Hardware Guide (MS2/Extra 3.4.x) Contents 1 Introduction..............................................................................................................................7 1.1 Emissions and disclaimer................................................................................................7 1.2 Required tools..................................................................................................................7 1.3 How to use this manual....................................................................................................7 2 Megasquirt System Hardware.................................................................................................9 2.1 Overview..........................................................................................................................9 2.2 Megasquirt Installation.....................................................................................................9 2.3 Wiring Harness...............................................................................................................10 2.4 Crank / Cam Inputs........................................................................................................10 2.5 Sensor Inputs.................................................................................................................10 2.6 Outputs...........................................................................................................................10 2.7 Tuning interface..............................................................................................................10 3 Wiring.....................................................................................................................................11 3.1 Best Practices.................................................................................................................11 3.1.1 Wire and connector choice.....................................................................................11 3.1.2 Soldering or crimping..............................................................................................11 3.1.3 Re-pinning the DB37...............................................................................................11 3.1.4 Fusing......................................................................................................................11 3.1.5 4-pin relay pin-out note...........................................................................................11 3.1.6 Relay and accessory power routing........................................................................11 3.2 Grounding (Earthing) Schemes.....................................................................................12 3.3 Core Wiring Diagram......................................................................................................13 3.3.1 Optional Connections.............................................................................................13 3.3.2 Relay Board............................................................................................................16 3.4 Inputs..............................................................................................................................18 3.4.1 Crank and Cam Tach inputs...................................................................................18 3.4.2 MAP (Manifold Absolute Pressure) sensor.............................................................18 3.4.3 IAT/MAT (Intake/Manifold Air Temperature) sensor................................................19 3.4.4 CLT (Coolant Temperature) sensor........................................................................22 3.4.5 TPS (Throttle Position Sensor)...............................................................................23 3.4.6 O2 (Oxygen) Sensor / Lambda Sensor..................................................................23 3.4.7 MAF (Mass Air Flow) Sensor..................................................................................25 3.4.8 Flex / Switch input...................................................................................................29 3.4.9 Spare ADCs / Switch inputs....................................................................................31 3.4.10 B/LD boot jumper..................................................................................................33 3.4.11 CAN comms..........................................................................................................34 3.4.12 Knock sensor........................................................................................................34 3.5 Outputs...........................................................................................................................36 3.5.1 Fuel Injector outputs...............................................................................................36 3.5.2 Ignition outputs.......................................................................................................36 3.5.3 Fuel pump output....................................................................................................36 3.5.4 Idle valve.................................................................................................................37 3.5.5 Tacho output...........................................................................................................40 3.5.6 Other relay outputs.................................................................................................41 (c) 2014-6 James Murray 2016-02-02 Page 3/186 MS2V3.57 Hardware Guide (MS2/Extra 3.4.x) 3.5.7 Boost control output................................................................................................41 3.6 Inputs and Outputs Summary........................................................................................42 3.6.1 Pin vs. feature table................................................................................................43 3.7 Bench test wiring............................................................................................................43 3.7.1 Minimal connection.................................................................................................43 3.7.2 JimStim connection.................................................................................................44 4 Fuel System...........................................................................................................................45 4.1 Introduction....................................................................................................................45 4.1.1 Existing EFI Vehicle................................................................................................46 4.1.2 Retro-fit EFI Vehicle................................................................................................46 4.2 Single Fuel pump...........................................................................................................46 4.3 Low pressure / high pressure - twin pump.....................................................................46