MS3Pro Ultimate is a 93-pin wire-in MegaSquirt / AMP EFI ECU on 3 connectors: White (35 pins), Gray (35 pins) and Black (23 pins).
It has 10 injector outputs and 8 ignition outputs. The injector drivers are peak-and-hold, so low-impedance injectors run without a resistor pack. The ignition outputs are logic-level. Smart coils plug straight in; dumb coils need an igniter in between.
There are 2 dedicated trigger inputs, each happy with a VR or a Hall sensor. Two knock inputs cover both banks of a V engine. Wideband control needs an external controller, usually over CAN. The MAP sensor is built in.
It does not drive an electronic throttle, so plan on a cable throttle. One CAN bus handles dashes, PDMs and expansion.
Spec sheet
| Connectors | White (35), Gray (35), Black (23)93 pins in this profile |
|---|---|
| Injector outputs | 10peak-and-hold (low-impedance capable) |
| Ignition outputs | 8logic-level: smart coils, or an igniter for dumb coils |
| Dedicated trigger inputs | 2VR or Hall |
| Knock inputs | 2 |
| Onboard wideband controllers | 0 |
| Onboard MAP sensor | Yes |
| CAN buses | 1 |
| Drive-by-wire | No |
| High-side outputs | 0 |
| Half-bridge outputs | 4H-bridge pairs for a throttle motor or stepper |
| 5V sensor supply | 2 pins |
Worth knowing
- The 4-pin H-bridge is a bipolar idle stepper driver, not drive-by-wire.
Which builds it suits
Of the 58 swap presets in the planner, 0 fit as they are and 27 fit with add-ons; 31 do not fit at all. The add-on it asks for most often is a CAN wideband module. Where it falls short, it is usually not enough drive-by-wire throttle motor (h-bridge). The planner fills anything a preset leaves open with its ordinary defaults, so your own build may land differently.
The Ford Modular 4.6 2V (SOHC) needs a CAN wideband module and an external igniter. The Subaru EJ/FA EJ20 turbo dual-AVCS (EJ207 GRB 2008+) needs a CAN wideband module. It can't run the GM LS2 (Gen4 6.0 alum): not enough drive-by-wire throttle motor (h-bridge). It can't run the Ford Modular 5.4 4V GT500 (S/C, DBW): not enough drive-by-wire throttle motor (h-bridge). It can't run the Subaru EJ/FA EJ25 turbo single-AVCS (EJ257 2004-07): not enough drive-by-wire throttle motor (h-bridge).
Fits with add-ons 27
- Toyota 1JZ-GE distributor (NA, early) with a CAN wideband module, an external igniter
- Toyota 1JZ-GE VVT-i (coil pack) with a CAN wideband module, an external igniter
- Toyota 1JZ-GTE non-VVTi with a CAN wideband module, an external igniter
- Toyota 1JZ-GTE VVTi with a CAN wideband module, an external igniter
- Toyota 2JZ-GE distributor (NA, early) with a CAN wideband module, an external igniter
- Toyota 2JZ-GE VVT-i (coil pack) with a CAN wideband module, an external igniter
- Toyota 2JZ-GTE non-VVTi with a CAN wideband module, an external igniter
- GM LS1 (Gen3 5.7 alum) with a CAN wideband module
- GM LS6 (Gen3 5.7 alum) with a CAN wideband module
- GM LS LQ4/LQ9 (Gen3 6.0 iron) with a CAN wideband module
- Ford Modular 4.6 2V (SOHC) with a CAN wideband module, an external igniter
- Ford Modular 4.6 4V Cobra (NA, cable) with a CAN wideband module, an external igniter
- Ford Modular 4.6 4V Terminator (S/C, cable) with a CAN wideband module, an external igniter
- Ford Modular 5.4 4V Ford GT (S/C, cable) with a CAN wideband module, an external igniter
- Nissan RB20DET with a CAN wideband module, an external igniter
- Nissan RB25DET non-Neo S1 (R33, dumb coils) with a CAN wideband module, an external igniter
- Nissan RB25DET non-Neo S2 (R33, smart coils) with a CAN wideband module
- Nissan RB25DET Neo (R34) with a CAN wideband module
- Nissan RB26DETT (R32/R33, dumb coils) with a CAN wideband module, an external igniter
- Nissan RB26DETT (R34, smart coils) with a CAN wideband module
- Nissan SR20DET (S13) with a CAN wideband module, an external igniter
- Nissan SR20DET (S14) with a CAN wideband module, an external igniter
- Nissan SR20DET (S15) with a CAN wideband module
- Subaru EJ/FA EJ20 turbo single-AVCS (EJ207 v7-9) with a CAN wideband module
- Subaru EJ/FA EJ20 turbo dual-AVCS (EJ207 GRB 2008+) with a CAN wideband module
- Mazda Rotary 13B-REW (FD RX-7) with a CAN wideband module
- Mazda Rotary 20B (Eunos Cosmo 3-rotor) with a CAN wideband module
Does not fit 31
- Toyota 2JZ-GTE VVTi not enough drive-by-wire throttle motor (h-bridge)
- GM LS2 (Gen4 6.0 alum) not enough drive-by-wire throttle motor (h-bridge)
- GM LS3 (Gen4 6.2 alum, car) not enough drive-by-wire throttle motor (h-bridge)
- GM LS L76 (Gen4 6.0 alum) not enough drive-by-wire throttle motor (h-bridge)
- GM LS L92 (Gen4 6.2 alum) not enough drive-by-wire throttle motor (h-bridge)
- GM LS LY6/L96 (Gen4 6.0 iron) not enough drive-by-wire throttle motor (h-bridge)
- GM LSA (Gen4 6.2 alum, S/C) not enough drive-by-wire throttle motor (h-bridge)
- GM LT1 (Gen5 6.2 alum) not enough drive-by-wire throttle motor (h-bridge)
- GM LT4 (Gen5 6.2 alum, S/C) not enough drive-by-wire throttle motor (h-bridge)
- Ford Coyote 5.0 Gen1 (2011-14) not enough drive-by-wire throttle motor (h-bridge)
- Ford Coyote 5.0 Gen2 (2015-17) not enough drive-by-wire throttle motor (h-bridge)
- Ford Coyote 5.0 Gen3 (2018-23) not enough drive-by-wire throttle motor (h-bridge)
- Ford Modular 5.4 4V GT500 (S/C, DBW) not enough drive-by-wire throttle motor (h-bridge)
- Ford Coyote Voodoo 5.2 (GT350, flat-plane) not enough drive-by-wire throttle motor (h-bridge)
- Ford Coyote Predator 5.2 (GT500, cross-plane, S/C) not enough drive-by-wire throttle motor (h-bridge)
- Ford Barra 4.0 NA (182/190/195) not enough drive-by-wire throttle motor (h-bridge)
- Ford Barra 4.0 Turbo (240T/245T/270T/310T/325T) not enough drive-by-wire throttle motor (h-bridge)
- Nissan VR38DETT (R35 GT-R) not enough drive-by-wire throttle motor (h-bridge)
- Nissan VQ35DE (base, 2003-04) not enough drive-by-wire throttle motor (h-bridge)
- Nissan VQ35DE Rev-Up (2005-06) not enough drive-by-wire throttle motor (h-bridge)
- Nissan VQ35HR (High-Rev, 2007+) not enough drive-by-wire throttle motor (h-bridge)
- Honda K20 (i-VTEC 2.0 NA) not enough drive-by-wire throttle motor (h-bridge)
- Honda K24 (i-VTEC 2.4 NA) not enough drive-by-wire throttle motor (h-bridge)
- Subaru EJ/FA EJ25 turbo single-AVCS (EJ257 2004-07) not enough drive-by-wire throttle motor (h-bridge)
- Subaru EJ/FA EJ25 turbo dual-AVCS (EJ257 2008+) not enough drive-by-wire throttle motor (h-bridge)
- Subaru EJ/FA FA20D (BRZ/86 NA) not enough drive-by-wire throttle motor (h-bridge)
- Subaru EJ/FA FA20DIT (WRX turbo 2015+) not enough drive-by-wire throttle motor (h-bridge)
- Mazda Rotary 13B-MSP Renesis (RX-8 manual, 6-injector) not enough drive-by-wire throttle motor (h-bridge)
- Mazda Rotary 13B-MSP Renesis (RX-8 auto, 4-injector) not enough drive-by-wire throttle motor (h-bridge)
- BMW S54 (3.2 NA I6, E46 M3) not enough knock inputs
- BMW N54 (3.0 twin-turbo I6) not enough drive-by-wire throttle motor (h-bridge)
Plan a build around the MS3Pro Ultimate
Pin table
By connector: White carries 2 injector outputs, 2 trigger inputs and 2 knock inputs; Gray carries 8 injector outputs, 8 ignition outputs and 2 trigger inputs; Black carries 1 analog input and 8 digital inputs.
Show all 93 pins
| Pin | Function |
|---|---|
| White 1 | High current out 1 |
| White 2 | High current out 2 |
| White 3 | Injector out J |
| White 4 | Injector out I |
| White 5 | High current out 3 |
| White 6 | CKP+ (crank) |
| White 7 | Knock In 2 |
| White 8 | 5V+ VREF out 1 |
| White 9 | TPS in |
| White 10 | MAT in (IAT) |
| White 11 | CLT in |
| White 12 | Analog In 6 |
| White 13 | Power ground |
| White 14 | PWM / Idle Out 1 |
| White 15 | CKP- (crank return) |
| White 16 | Logic ground |
| White 17 | Analog In 7 |
| White 18 | Sensor return |
| White 19 | Analog in 1 |
| White 20 | Analog in 2 |
| White 21 | Analog in 3 |
| White 22 | Analog In 4 |
| White 23 | Analog In 5 |
| White 24 | Tach out |
| White 25 | O2 in |
| White 26 | CMP+ (cam) |
| White 27 | CMP- (cam return) |
| White 28 | Fuel pump relay out |
| White 29 | PWM out 2 |
| White 30 | PWM out 3 |
| White 31 | Knock in 1 |
| White 32 | Digital switched in 1 |
| White 33 | CAN L |
| White 34 | CAN H |
| White 35 | 12V+ switched power in |
| Gray 1 | Injector out A |
| Gray 2 | Injector out B |
| Gray 3 | Ground |
| Gray 4 | Injector out C |
| Gray 5 | Ground |
| Gray 6 | Injector out D |
| Gray 7 | Ground |
| Gray 8 | Injector out E |
| Gray 9 | Ground |
| Gray 10 | Injector out F |
| Gray 11 | Injector out G |
| Gray 12 | Injector out H |
| Gray 13 | Spark out G |
| Gray 14 | Spark out E |
| Gray 15 | Spark out C |
| Gray 16 | Spark out H |
| Gray 17 | Digital frequency in 2 |
| Gray 18 | Ground |
| Gray 19 | Digital switched 12V in |
| Gray 20 | Digital switched in 2 |
| Gray 21 | Digital frequency in 3 |
| Gray 22 | Digital Frequency in 3 VR+ |
| Gray 23 | Digital Frequency In 3 VR- |
| Gray 24 | Spark out F |
| Gray 25 | Spark out B |
| Gray 26 | Spark out D |
| Gray 27 | Spark out A |
| Gray 28 | Digital frequency in 1 |
| Gray 29 | Digital switched in 3 |
| Gray 30 | Stepper IAC out 1B |
| Gray 31 | Stepper IAC out 1A |
| Gray 32 | Stepper IAC out 2A |
| Gray 33 | Stepper IAC out 2B |
| Gray 34 | Digital Frequency in 1 VR+ |
| Gray 35 | Digital Frequency in 1 VR- |
| Black 1 | PWM out 5 |
| Black 2 | PWM out 4 |
| Black 3 | Digital out 2 |
| Black 4 | Digital out 1 |
| Black 5 | Digital I/O 4 |
| Black 6 | Digital I/O 2 |
| Black 7 | Analog in 8 |
| Black 8 | 5V+ VREF out 2 |
| Black 9 | Fuel only coil negative |
| Black 10 | Digital switched in 5 |
| Black 11 | Digital switched in 4 |
| Black 12 | Digital I/O 5 |
| Black 13 | Digital I/O 3 |
| Black 14 | Digital I/O 1 |
| Black 15 | 5V+ VREF out 2 |
| Black 16 | Fuel only battery 12V+ |
| Black 17 | Sensor return |
| Black 18 | Sensor return |
| Black 19 | Sensor return |
| Black 20 | Sensor return |
| Black 21 | Sensor return |
| Black 22 | 5V+ VREF out 1 |
| Black 23 | Keep alive power |
Other MegaSquirt / AMP EFI ECUs
The closest MegaSquirt / AMP EFI unit is the MicroSquirt V3. Against it, this one has 10 injector outputs (the MicroSquirt V3 has 2), 8 ignition outputs (the MicroSquirt V3 has 2), 2 knock inputs (the MicroSquirt V3 has 0) and 93 pins (the MicroSquirt V3 has 35).
Source: MegaSquirt / AMP EFI document AMP EFI MS3Pro Ultimate manual v1.210 (ampefi.com, the profile source_url)
Always verify against the manufacturer's manual and your tuner before wiring.