For the FD select (series 6) what exactly are the inputs/outputs used for? Are there any extras available? I have an almost stock car with full rats nest.

I've seen mention in other threads that it controls both the stock MOP and stock twin turbos, so
- MOP (4 control lines)
- Turbos:
-- turbo control
-- charge control
-- charge relief
-- turbo pre-control
-- wastegate
- Idle air control valve
That makes 10 outputs, but the 440 only has 8 outputs available, so how does that work?
Are some of the MOP outputs redundant, and it doesn't actually require 4 ECU outputs? Are the turbo control and charge control solenoids switched from the same ECU output using an off-chip relay? Does the FD Select not actually control the stock wastegate and turbo pre-control solenoids, and I would need a separate boost controller?

Also, what is done for other stock solenoids/relays that are controlled by the stock ECU:
- Double-throttle solenoid - is it just wired to constant 12V, and not switch based on temperature like the stock ECU does?
- PRC - not used? are hot starts not an issue because of better fuel control?
- A/C relay - not connected? so no A/C shutoff during acceleration like stock?
- Fuel pump relay - I assume the main relay must be wired to get 12V with ignition, right? What about the secondary relay that boosts the fuel pump voltage?
- Purge control solenoid - always on with ignition?
- Emissions: Air pump, ACV, EGR - not connected? always on? always off?

And for inputs - are there extra digital inputs available? If so, how do you access them?

My main concern is I need to be able to pass smog checks; if necessary I could swap back to the stock ECU, but ideally I'd like (hypothetically of course) to get an aftermarket ECU that I could leave in for the test. I need to leave most or all of the smog equipment and rat's nest intact (although it doesn't really all need to be hooked up; for example I don't think the EGR even engages during a smog check).
Would I need a 1280 to accomplish this? Would you be willing to make a patch harness for the 1280 that would plug into the stock ECU connectors, and leave flying leads for the extra inputs/outputs?

 

Hello,

The MOP takes 2 outputs. The stepper motor coils are driven in anti-phase so you only need 2 “control” outputs from the ECU (one always follows the other).

These are aux outputs 7 and 8.



Turbo control:

Precontrol is its own output (aux 1) (little flap in the exhaust manifold to allow a little bit of air to prespool the 2nd turbo)

Turbo control, aux 4, drives the following outputs:

- Turbo control solenoid valve (main flap in the exhaust manifold)

- Charge relief solenoid valve (so that the 2nd turbo is allowed to vent during the precontrol phase)

- This output is also inverted, and used to drive the Charge Control solenoid valve (turning this output ON closes up the outlet of the 2nd turbo, so when we’re on the first turbo, this output has to be ON all the time – opposite of the turbo control solenoid valve)



So yes, your guess about controlling multiple outputs from one source was correct, but we don’t use relays inside the ECU.



Idle control is on aux 2, and wastegate / boost control is on aux 3



Fuel pump on/off is on aux 5 – and fuel pump always runs at full speed

Thermofan is on aux 6



Double throttle solenoid – actually you need to leave that open circuit for it to always allow all 3 throttles to move, and that’s what we do (pin 3O on the ECU, not connected).



PRC – not used, yes we can control things like post-crank enrichment to compensate if necessary.



A/C – normally we would control this through the ECU so we can disable it during cranking, at WOT etc, but as you noticed we didn’t have enough outputs to do that so instead it follows the input from the A/C request input.



Purge isn’t always on, we don’t drive it at all, because it tends to mess up the mixtures at idle if you do that (sucking the fuel vapor off the carbon). We also don’t drive the air pump, ACV, EGR.



A 1280 could do it all, but it would be a LOT of work to set it all up( not Plug and Play either)



I think the easiest way to get it through smog would be to run the port air injectors and the air pump all the time. I’m not sure about EGR. The FD engine has a LOT of overlap, even from factory, so plenty of fuel goes straight through the engine. Even from factory at idle they run about 11:1 AFR. The way they get the missions down is running 2 cats in series and injecting enough air to burn up the excess fuel in the cat, or adding alcohol to the tank( but this is tricky).

 

Thanks for the detailed answer, that really clears things up for me. I think I'll be trying one of these shortly.

A couple additional questions:
Why do you use an output for the fuel pump instead of just wiring it to come on with the ignition? Is this a safety thing, where the pump turns off when the engine stops? If so, is there a way to manually tell the ECU to run the pump to pressurize the fuel system for testing/diagnostic purposes?
It looks like all the inputs are already used? I converted my steering to a manual rack, so can I reprogram the DIGIN3 input for other things, like switching between maps? I'm installing a water injection system that has a failure output, so I'd like to hook that up to the ECU to put it into a "limp" mode.

 

Hi YellowT2,

Yes connecting the fuel pump to an Aux Output is safer. It primes the pump before cranking, and once running, it will only keep the pump on if it sees an RPM signal. You can toggle the aux outputs on/off by using the "invert" tickbox in the software.

If you're not running power steering, then yes you can do that with Digital Input 3. But I think Digital Input 5-8 may be free to use as well, I know they're connected to something in the schematic, but they didn't have functions set up when I looked at the base map.