FuelTech FT400 pinout
ecurecovery.com/pinouts/fueltech/ft400 · Every pin checked against 2 FuelTech documents · data checked 2026-11-04
FuelTech FT400 pinout
Every pin of the 24-pin MAIN and 16-pin AUX connectors, with the wire colours of FuelTech's harness. Tap a pin to see what it does.
Every pin checked against 2 FuelTech documents- Connector MAIN · 24-pin
- Connector AUX · 16-pin
FuelTech's documents list the pins but do not draw the plug, so we do not draw it either.
Pick any pin in the table to see its function and the documents it was checked in.
FuelTech FT400 connector MAIN pinout (24-pin)
| Pin | Function | Wire | FuelTech note |
|---|---|---|---|
| MAIN-1 | Tachometer output | Green | RPM signal output for tachometers and auxiliary modules. |
| MAIN-2 | Auxiliary output 3 | Yellow – 3Yellow | Must be configured prior to the installation. |
| MAIN-3 | Input 1 – intake air temperature Sensor | White/Blue | The other sensor pin must be connected to the negative. |
| MAIN-4 | Auxiliary output 2 | Yellow – 2Yellow | Must be configured prior to the installation. |
| MAIN-5 | Input 2 | White | Must be configured according to the sensor used. FT400: connected to the fuel pressure sensor. FT350: configurable as fuel or oil pressure or O2 sensor input |
| MAIN-6 | Auxiliary output 1 | Yellow – 1Yellow | Must be configured prior to the installation. |
| MAIN-7 | Input 3 – engine coolant temperature sensor | Pink | The other sensor pin must be connected to the negative. |
| MAIN-8 | Auxiliary output 4 | Yellow – 4Yellow | Must be configured prior to the installation. |
| MAIN-9 | Input 4 | Blue | Must be configured in accordance with the sensor or function used. FT400: connected to the oil pressure sensor. FT350: configurable as fuel or oil pressure or 2-step input |
| MAIN-10 | Ignition output E | Gray – EGrey | |
| MAIN-11 | Signal from the TPS sensor TPS 1 for electronic throttle | Orange | Connect the 3 TPS wires in a way which, when measuring the resistance between the green/red and black wires in the cable, the value does not vary. |
| MAIN-12 | Ignition output D | Gray – DGrey | |
| MAIN-13 | MAP signal output | Yellow/Red | Connected to a datalogger, it informs the pressure/vacuum read by the injection inner MAP. |
| MAIN-14 | Ignition output C | Gray – CGrey | |
| MAIN-15 | Camshaft position sensor input | Green/Yellow | It reads inductive or Hall effect sensors. It must be configured prior to the installation. |
| MAIN-16 | Ignition output B | Gray – BGrey | |
| MAIN-17 | RPM signal input | - | Must be connected to the crankshaft trigger sensor (inductive or Hall) or to the Hall distributor – Discard shield |
| MAIN-18 | Ignition output A | Gray – AGrey | |
| MAIN-19 | Battery’s negative terminal | Black, ShieldBlackShielded | Must be directly connected to the battery; no add-ons or seams allowed. Cannot be connected to vehicle chassis. |
| MAIN-20 | 5V feed for sensors | Green/Red | Feed for TPS, as well as other sensors. |
| MAIN-21 | Switched 12V supply | Red | Connect directly to ignition switch. |
| MAIN-22 | Power Ground | Black/White | Connected directly to the battery negative, seamlessly. Do not join this wire with the black wire before the battery terminal. They can only |
| MAIN-23 | Negative terminal from fuel injectors – Bank “B” | Brown | See chapter 6 in this manual for more information about these outputs and their connections. |
| MAIN-24 | Negative terminal from fuel injectors – Bank “A” | Purple | See chapter 6 in this manual for more information about these outputs and their connections. |
FuelTech FT400 connector AUX pinout (16-pin)
| Pin | Function | Wire | FuelTech note |
|---|---|---|---|
| AUX-1 | O2 sensor input | White #1White | Connected to a wideband lambda O2 conditioner analog output or to a narrowband O2 sensor. |
| AUX-2 | Ignition output F | Gray – FGrey | |
| AUX-3 | Electronic throttle TPS 2 | Orange #2Orange | When used with electronic throttle, it must be connected to the throttle’s TPS 2. |
| AUX-4 | Auxiliary output #7 | Yellow #7Yellow | It must be configured prior to the installation. |
| AUX-5 | Two-Step input | White #2White | Two-step button (activated by negative signal). |
| AUX-6 | Auxiliary output #6 | Yellow #6Yellow | It must be configured prior to the installation. |
| AUX-7 | A/C button input | White #3White | Air conditioning actuation signal. It must be connected to the A/C button on the dashboard. The actuation polarity can be configured. |
| AUX-8 | Auxiliary output #5 | Yellow #5Yellow | It must be configured prior to the installation. |
| AUX-9 | Power ground | Black/white | Connected directly to the battery negative, seamlessly. Do not join this wire with the black wire before the battery terminal. They can only |
| AUX-10 | PEDAL signal #1 | Orange/Blue #1Orange/blue | It must be connected to the pedal position sensor PEDAL1. |
| AUX-11 | Throttle or pedal ground output | Green/Black | Connected to the TPS or the pedal sensor. When not using electronic throttle, connect this wire to battery negative. |
| AUX-12 | PEDAL signal #2 | Orange/Blue #2Orange/blue | It must be connected to the pedal position sensor PEDAL2. |
| AUX-13 | Electronic throttle motor #1 Step motor (coil #1) | Brown/White #2Brown/white | To constitute the MOTOR 1 wire, join both Brown/White wires and connect to the throttle. |
| AUX-14 | Electronic throttle motor #2 Step motor (coil #2) | Purple/White #2Purple/white | To constitute the MOTOR 2 wire, join both Purple/White wires and connect to the throttle. |
| AUX-15 | Electronic throttle motor #1 Step motor (coil #1) | Brown/White #1Brown/white | To constitute the MOTOR 1 wire, join both Brown/White wires and connect to the throttle. |
| AUX-16 | Electronic throttle motor #2 Step motor (coil #2) | Purple/White #1Purple/white | To constitute the MOTOR 2 wire, join both Purple/White wires and connect to the throttle. |
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Check my map freeFuelTech FT400 pins at a glance
- Which pins are the crank and cam inputs on the FuelTech FT400?
- Camshaft position sensor input: pin MAIN-15 (Green/Yellow). RPM signal input: pin MAIN-17.
- Which pins are the injector outputs on the FuelTech FT400?
- Negative terminal from fuel injectors – Bank “B”: pin MAIN-23 (Brown). Negative terminal from fuel injectors – Bank “A”: pin MAIN-24 (Purple).
- Which pins are the ignition outputs on the FuelTech FT400?
- Ignition output E: pin MAIN-10 (Gray – E). Ignition output D: pin MAIN-12 (Gray – D). Ignition output C: pin MAIN-14 (Gray – C). Ignition output B: pin MAIN-16 (Gray – B). Ignition output A: pin MAIN-18 (Gray – A). Ignition output F: pin AUX-2 (Gray – F).
- Which pins are ground on the FuelTech FT400?
- Power Ground: pin MAIN-22 (Black/White). Power ground: pin AUX-9 (Black/white).
- Which pins power the FuelTech FT400?
- Switched 12V supply: pin MAIN-21 (Red).
- Which pins are the sensor supplies on the FuelTech FT400?
- 5V feed for sensors: pin MAIN-20 (Green/Red).
FuelTech FT400 pinout sheet
A printable sheet with every pin, made from the checked data on this page.
Where this comes from
Only FuelTech's own documents. Pin names and notes are written exactly as FuelTech writes them.
FuelTech manual for this ECU (harness connections table)
FuelTech FT450 / FT550 / FT600 manual, chapter 9: the old harness wire by wire
FuelTech connector drawing in the same manual, read by eye
How we checked it
- We start from the pin table in FuelTech's manual for this ECU: pin, wire colour and function.
- Every pin is read again in a second FuelTech document: its harness manuals, which list each ECU pin with its wire colour, or for the FT700 its quick reference. A script compares them pin by pin.
- A pin is only shown when the second document gives the same wire colour and function. FuelTech names its general-purpose wires by colour and number (Blue #1 is blue output 1), so the number has to match too.
- Labels, notes and wire colours are written exactly as FuelTech writes them.
Where FuelTech's documents disagree
MAIN 13: FuelTech's FT550 manual (chapter 9.2, the old FT400 harness wire by wire) leaves this wire out. The FT400 manual lists it in its pin table and on its connector drawing ('MAP Signal Output - Yellow/Red').
AUX 6: the FT400 manual's table prints 'Auxiliary output #7' on this pin. Its wire number, its own connector drawing and FuelTech's FT550 manual all say 'Auxiliary output #6'. Shown: 'Auxiliary output #6'.
AUX 8: the FT400 manual's table prints 'Auxiliary output #7' on this pin. Its wire number, its own connector drawing and FuelTech's FT550 manual all say 'Auxiliary output #5'. Shown: 'Auxiliary output #5'.
AUX 11: FuelTech's FT550 manual (chapter 9.2, the old FT400 harness wire by wire) leaves this wire out. The FT400 manual lists it in its pin table and on its connector drawing ('Throttle or Pedal Ground Output - Green/Black').
ECU Recovery is not affiliated with FuelTech. FuelTech and its product names are trademarks of FuelTech. If your harness came with its own diagram, check your wiring against it.
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