TheHoffmann

So hypothetically, if I were to purchase the bulk dash harness for an 07 LGT that came equipped with a manual transmission or even a crashed SpecB, (with or without ecu, and a key with the immobilzer), install it along with a jdm 6-speed or even a US-spec 2008 6-speed transmission into my 07 LGT that came equipped with a 5eat. It would work fine? And would I potentially keep those features like Cruise control as well?

As far as I understand you don't need the bulkhead harness if you are just swapping for a manual. You may need to repin your ecu to fit the manual pinout, and flash your rom but that's about it.

I had to switch ecu's because I added a turbo, but for just a mnaual swap I don't think you need a new ecu.

Glad I found this thread and happy to hear everything is working well. I just bought a full spec b 6mt for my 05 wagon and am having a shop install it this September. Curious about of things though. I definitely want my cruise control to work, and what about the pedal box, trying to figure out what will work, any suggestions, Also should I upgrade the throw out bearing, clutch fork, and flywheel?

Flash a manual rom onto you ecu and you're good to go. I replaced everything so it was new, but I got a lightened flywheel for some better revving.

Ok, searched the forums on how to pull the map of the ecu. I found a stock jdm lgt manual map on the romraider forums, flashed it to my car and everything is working 100%.

No more Er Hc codes, cruise works, 100% throttle pedal equals 100% throttle plate...Couldn't be happier, gonna log some cold start values to make sure everything works as intended, then it's of to get engineered

Thanks for all the help guys

Do you have SI drive? It's limited to 80% or so in I mode... Shouldn't be an issue on an 05.

 

Also, if it's in limp mode due to a CEL or anything like that, it feels pretty weak and AVCS doesn't work.

Tactrix cable just arrived, immediately jumped in the car and checked the ecu. AVCS does seem to NOT work, cruise doesn't work and throttle body does only do 35% max. I do not have SI drive, but the donor car maybe had SI drive, I don't know (just bought the ecu).

Actually 05-09 all have mostly the same CANBUS with respect to the TCM. It's just not accessible on the OBD2 port prior to 2008. It's still there, just less of it and it's more hidden.

 

The Er HC codes I've heard are common with the these swaps. I would definitely try the manual ROM and manual/auto identifier pin first on that front. I'm not sure if there is more wiring between auto and manual for the EJ25. I haven't looked into it. If so, you'll probably have to start replacing or replicating wire harnesses, switches, etc. The cruise control is also probably looking for the clutch switch (so you can disable cruise when you push the clutch in).

Yeah tried the manual pin, but Er HC Codes are there, cruise doesn't work and somehow my throttle doesn't work 100%. If I flash to the manual and the codes are gone, thats already a win.

I did wire cruise up the right way, but gonna check when the new map is flashed.

Does somebody have an idea why the throttle would't open 100% when you push the pedal 100%? Either the actual valve is shot or wiring...

As long as the ECU has the AT ROM the vehicle will continue to try and communicate with the TCU and think the car is an auto. Flex fuel is not available for the AT and I wanted to be able to run flex (really just a failsafe mode for E60 and lower).

 

The pin you are talking about in the ECU made no difference, I did try that.

Ah I see, ordered a tactrix so gonna flash my auto to a manual rom. This explains why I get Er HC Codes in my dash. Will my cruise work after the flash or do I have to change something else? Is a 05 ecu

Did the donor 2005 LGT already have a transmission swap before it came to you? The 2005 LGT never came in a 6MT, it only ever had a 5MT. It wasnt until 2007 that Legacys were available with a 6MT, only on the Spec B model. I note this in case you did not know or if any future reader of this post was not aware.

 

As for flashing an MT rom over a AT rom, yes this is do-able. You just need to flash over with the same model year rom as the ECU matches. The key here is the first 4 characters of the ROM ID need to match (Example: A2WC521C can be over written with A2WC500N, but not A2UG000B).

Why dou you have to flash a manual rom onto the auto ecu? Afaik If you ground the TCM pin the ecu knows it's in manual mode. or are there different manual modes? Like cruise control for example not working...

Getting closer. Everything is pulled from the donor car and I sourced the rest of the parts I needed including a set of Spec B front/rear axles (donor was missing rears) and we discovered the reverse lockout cable on the donor was junk when we pulled the trans. Also picked up a 15+ STI rack and a set of aluminum control arms to swap while were at it. Hoping to start Thanksgiving week, congestion in the shop is what is preventing us from moving forward.

 

Got an updated tune for when we unmarry the AP and Pretty sure I have the wiring piece figured out, but time will tell with that. The biggest issue I have is transporting it. We are getting into winter blends here and if E content drops too low she won’t be going anywhere with my 10:1 CR.

Just found this thread and happens to be mostly the same as what I'm trying right now. Swapped an ej20y engine into my na legacy, and with it the 6mt. Got myself an auto gt ecu, and need to flash a manual rom aswell and rewire it. May I ask if you wired it since and where you got the right wiring diagram? And how difficult is it to flash the manual rom (or where to get one)?