ECU Pinout Planner
FAQ
How the ECU Pinout Planner gets from an engine spec to a pin sheet, and straight answers to the questions people ask on the way.
How it works
What the planner actually does
Most people choose a standalone ECU backwards: brand first, count later. The planner runs it the other way round. You describe the engine, it derives the inputs and outputs that build needs, and only then does it name a box.
- Describe the build. Start from an engine preset or from scratch. The guided flow asks about the things that change the pin count: injectors, coil type, trigger pattern, cam control, drive-by-wire and the sensors you are keeping. Not the things that look good on a spec sheet.
- Get the I/O tally. Injector drivers, ignition outputs, trigger inputs, analogue and temperature inputs, low-side and half-bridge outputs: counted by type as well as by number, with 5V-reference and sensor-ground fan-out counted rather than assumed.
- Shortlist the ECU. Wire-in ECUs are scored against that tally. Where one falls short, the planner names the shortfall, and whether an add-on module can close it, instead of just marking it red.
- Plan the pins. Pick one and it lays out a pin-by-pin connection sheet you can export or print and take to the bench.
Questions that come up
Does the planner save my build?
No. It runs entirely in your browser, and nothing you enter is sent anywhere or kept between visits. Export or print the connection sheet before you close the tab.
Where does the pinout data come from?
Each ECU profile is transcribed from the manufacturer’s own manuals and pinout documents, one pin at a time. Transcriptions can be wrong and hardware revisions change, so the manual for your exact ECU and revision wins any disagreement. If you find an error, tell us which pin.
Why does it count trigger inputs separately from digital inputs?
Because a crank or cam sensor needs a trigger-capable input, and a VR sensor needs one that can read VR. A spare digital input does not help. Counts are the easy part; types are the trap.
Does it cover plug-in ECUs?
No, wire-in only. That is where the pin planning is hard. A plug-in uses the factory connector, so the mapping is already done for you.
Is it free?
Yes. The adverts pay for it. They sit around the planner, never inside it.
Does it replace my tuner?
No. It gets you to a shortlist and a connection sheet faster than a napkin does. Your tuner has seen the car; the planner has not.
Always verify against the manufacturer’s manual and your tuner before wiring.