MS3 Gold Box V1.2 Hardware Manual Megasquirt-3 Product Range MS3 1.4.x Dated: 2016-05-18 Hardware manual covering specific wiring and configuration of your Megasquirt MS3 Gold Box. This version of the documentation applies to: • EFI Source MS3 Gold Box V1.2 as shown above running firmware MS3 1.4.x See the Setting Up manual for more detail on version numbers. Does not apply to other Megasquirt products or other firmware versions. (c) 2015-6 EFI Source / James Murray MS3-Gold Box V1.2 Hardware Guide Table of Chapters 1: Introduction.............................................................................................................................8 2: MS3 Gold Box System Hardware........................................................................................10 3: Wiring...................................................................................................................................12 4: Fuel System..........................................................................................................................53 5: Ignition System - fundamentals............................................................................................62 6: Ignition system - specific operating modes..........................................................................93 7: Throttles..............................................................................................................................168 8: Optional Hardware.............................................................................................................169 9: Example wiring...................................................................................................................170 10: Further information...........................................................................................................175 11: Appendix A: junkyard guide to finding EDIS.....................................................................176 12: Revision history................................................................................................................181 (c) 2015-6 EFI Source / James Murray 2016-05-18 Page 2/181 MS3-Gold Box V1.2 Hardware Guide Contents 1: Introduction.............................................................................................................................8 1.1 Emissions and disclaimer................................................................................................8 1.2 Required tools..................................................................................................................8 1.3 How to use this manual....................................................................................................8 2: MS3 Gold Box System Hardware........................................................................................10 2.1 Overview........................................................................................................................10 2.2 MS3 Gold Box Installation..............................................................................................10 2.3 Wiring Harness...............................................................................................................10 2.4 Crank / Cam Inputs........................................................................................................11 2.5 Sensor Inputs.................................................................................................................11 2.6 Outputs...........................................................................................................................11 2.7 Tuning interface..............................................................................................................11 3: Wiring...................................................................................................................................12 3.1 Best Practices................................................................................................................12 3.1.1 Wire and connector choice.....................................................................................12 3.1.2 Soldering or crimping..............................................................................................12 3.1.3 Re-pinning the ECU plugs......................................................................................12 3.1.4 Fusing.....................................................................................................................12 3.1.5 4-pin relay pin-out note...........................................................................................12 3.1.6 Relay and accessory power routing.......................................................................12 3.2 Grounding (Earthing) Schemes.....................................................................................12 3.3 Core Wiring Diagram......................................................................................................14 3.3.1 Connectors..............................................................................................................14 3.3.2 Gray plug................................................................................................................17 3.3.3 Black plug...............................................................................................................19 3.3.4 Injector / Coil Wire markings...................................................................................20 3.3.5 Spare connections..................................................................................................20 3.4 Inputs..............................................................................................................................23 3.4.1 Crank and Cam Tach inputs...................................................................................23 3.4.2 MAP (Manifold Absolute Pressure) sensor.............................................................23 3.4.3 IAT/MAT (Intake/Manifold Air Temperature) sensor................................................24 3.4.4 CLT (Coolant Temperature) sensor........................................................................27 3.4.5 TPS (Throttle Position Sensor)...............................................................................27 3.4.6 O2 (Oxygen) Sensor / Lambda Sensor..................................................................28 3.4.7 MAF (Mass Air Flow) Sensor..................................................................................30 3.4.8 Flex / Switch input...................................................................................................35 3.4.9 Spare Analog (ADC) inputs.....................................................................................36 3.4.10 Switch inputs.........................................................................................................37 3.4.11 'BOOT' jumper.......................................................................................................38 3.4.12 CAN comms..........................................................................................................38 3.4.13 Knock sensor........................................................................................................38 3.4.14 PT4, PT5 inputs / outputs.....................................................................................39 3.4.15 Speed sensor inputs.............................................................................................39 3.4.16 Barometer sensor.................................................................................................40 (c) 2015-6 EFI Source / James Murray 2016-05-18 Page 3/181 MS3-Gold Box V1.2 Hardware Guide 3.5 Outputs...........................................................................................................................41 3.5.1 Fuel Injector outputs...............................................................................................41 3.5.2 Ignition outputs.......................................................................................................42 3.5.3 Fuel pump output....................................................................................................42 3.5.4 Idle valve.................................................................................................................42 3.5.5 Tacho output...........................................................................................................45 3.5.6 Mid current PWM / relay or lamp output.................................................................46 3.5.7 Alternator control wiring..........................................................................................47 3.6 Bench test wiring............................................................................................................51 3.6.1 Minimal connection.................................................................................................51 3.6.2 JimStim connection.................................................................................................51 4: Fuel System..........................................................................................................................53 4.1 Introduction....................................................................................................................53 4.1.1 Existing EFI Vehicle................................................................................................54