I'm almost done swapping the transmission on my '11 Ralliart, but the car won't start. I've replaced the engine and front harnesses with X GSR ones from the same year, but various things don't work, namely no ignition signal, injectors stuck high, air intake sensor high, throttle motor high (horrible noise too).

I'm reading that I need to do some rewiring, but I can't find any Ralliart diagrams, so I'd rather just buy the right ECU.

The question is: obviously a Evo ECM would play nicely with Evo harnesses, but would it play nicely with the rest of the car?

Also does the year matter? Everything in there right now is 2011, but specifically for ECM year/trim?

 

The ECU pinout is the same for both Evo and Ralliart, so it shouldn't fix your problem. What is your original ROM ID and which one are you using right now? Have you reprogrammed ETACS yet?

 

Honestly, I couldn't tell you. I wasn't able to read the ROM from the car properly (idk why). It should be something like 56940007-10 (USDM Ralliart). I ended up going off of these as a basemap, then copy/pasted maps for fuel/timing/etc. (obv gonna tune later). 56940007 is what I'm using now.

Does the wiring change between models like that?

I haven't been able to get ETACSdecoder to work for ****, so I was planning on bringing it to the dealer later on.

 

You need to use a manual transmission ROM and customize your ETACS so it won't try to communicate with SST transmission. There's an alternative for ETACS decoder, google for MMCodingWriter.

 

Ok I'll give that a shot. Would changing transmission types affect which pins send what (or something like that)? Or could it be an incompatibility on the receiving end of the ECU?

 

Well, not the position of the pins, but the output is always based on the inputs. The ECU communicates with SST and ETACS all the time through CAN bus and the received information will affect the calculations which will result in the output for the actuators.

 

Alright, so I was able to flash the ETACS unit, and now the the transmission warnings are gone

However, still no dice on the starting. The errors remain:
P0183 Fuel tank temperature sensor circuit high input
P0113 Intake Air Temperature Sensor High Input
P0123 Throttle Position Sensor (main) Circuit High Input
P0222 Throttle position sensor (sub) circuit low input

EDIT: to clarify, I had the ECM set to M/T before in the tune, AFAIK

 

Alright. ROM ID 56940007 is for USDM Ralliart, that's why I suggested you to flash a manual transmission Evo ROM.
Do you know if your car has a fuel temperature sensor? Some non-US versions doesn't have.
For the TPS errors, check if ECU pin 13 is grounded and if pin 12 is providing 5v when ACC is on.
For IAT error, do the same for pins 88 (ground) and 89 (5v approximately).
You can check TPS and MAF connectors first, which will be easier to do. Take a look at the service manual for the pinout.

 

Unfortunately I can't flash an Evo ROM, you get "can't write to protected area" in ECUflash. Is there some specific tables/something from the Evo ROM I should be copying over, instead?

I'll take a look at the pins and report back. Thanks for the help.

 

You should do a bench reflash. The ROM "program" itself is probably different, it's not a matter of copying tables over.

 

12 and 13 are good to go, 88 and 89 are no ground (?) and ~1.3v.

I don't know anywhere nearby who could do a bench for me, and I don't have a power supply. In that case, would it make sense to buy a GSR ECM, then flash that with M/T tune?

 

It's an option. You will have to code your VIN to the "new" ECU.
You can also do the bench flash using your car battery, if it's good enough.

 

Hmm alright. I only get the weekends to work on her, so getting an ECU might be less work, but I'll it a shot. If I do get a new one, I'm assuming any year for the X GSR or MR should work?

As for the tuning, does any ROM ID work as long as it fits the bill?

For the IAT still being janked, you think there's any reason to worry, or just one of those "eh it'll probably fix with the ECU" kind of things?

Thanks again

 

An MR ECU would require a bench flash anyway, so you will be looking for an GSR ECU. It's safer to keep the same year as your wiring harness, but any year should work. The same goes for the ROM ID. Regarding the IAT error code, check if you get a valid reading through Evoscan. Next step should be to check the harness continuity. But it can go away with the new ROM/ECU.

 

Solid. If I get the IAT error after that, I'll just bring her to the dealership haha. Thanks man!
I'll be sure to put up a build guide... If I ever finish