Gearshift Maps

[longassname]

Thanks,

I've been naughty and nice. Is that good enough for a set of glass headlamps?

The owner is a member of these forums. I'm sure he'll be able to come up with the number. Do you by any chance have a jdm svx tcu to sell him?

[longassname]

In case it actually means anything to anyone. I just download the firmware off that tcu and its ROM ID is 745913

[longassname]

Phil,

I'm going to be sending a bunch of bins your way soon. Do you want them one or two at a time or about a dozen or so at once?

[longassname]

the label on the rom is e54jv4bb

[NeedForSpeed]

Originally Posted by longassname

Thanks,

I've been naughty and nice. Is that good enough for a set of glass headlamps?

The owner is a member of these forums. I'm sure he'll be able to come up with the number. Do you by any chance have a jdm svx tcu to sell him?

As for the naughty and nice, probably good enough Just moved again, have stuff all over the State now. When I get it sorted, I'll send you a PM, but it won't be 'til early summer.

As for a JDM SVX TCU, maybe, depending on which trans he has? Please ask him to send a PM.

All-righty-then, back to the thread at hand

[longassname]

Ok, he says it's a 93 JDM WRX transmission and computer..so at least now we can add that to the library of firmware propperly identified. I asked him to pm you, Ron, to see about getting a JDM SVX TCU because it sounds to me like this tcu isn't for/the transmission didn't come with a US/JDM SVX style 3 wire speed sensor.

[cdvs]

For information only:
I have a TCU that apparently is FWD. It has a big FC on the outside (compare to FB for the AWDs that I have). The board is missing power transistors Q523 and Q526, but otherwise looks the same. The Rom is marked E31UF1D0.

[b3lha]

Wow. I go away for a week and so many replies to the threads.

We now know that

FA is early model
FB is USDM AWD
FC is USDM FWD
FF is early model UK/Aust.

I wonder if there was ever an FD or FE version?

Michael,

If roms are only 16K each then I should have enough space in my mailbox for all of them.

Phil.

[b3lha]

I suspect I'm going to regret posting this, but I finally found confirmation of Harvey's discovery that Subaru changed the type of C solenoid on late-model VTD boxes.

The early model UK rom, 705622, calculates the Sol.C duty cycle and stores it at address 0079 as a number between 0 and 20000. For example, 1000=5%, 19000=95%.

The later model UK rom, 705625, calculates the duty cycle and stores it at address 0100. Then this bit of code subtracts it from 20000 and stores the result at address 0079. So a calculated 95% cycle (19000) becomes (20000-19000=1000) 5% to drive the solenoid.

d9ba fc c0 05    ldd (0xC005) ; value 20000 at this address
d9bd b3 01 00    subd (0x0100)
d9c0 dd 79       std (0x0079)
d9c2 39          rts

So, if you have an early VTD box, you need a matching early TCU. If you have a late VTD box you need a matching late TCU.

We have the early and late UK roms, but only the early JDM rom, not the late one. If somebody had a late JDM box but no matching TCU, it should be fairly simple mod to make the early JDM code to work with a late JDM box.

[cdvs]

Thanks, Phil. This is personally helpful.

As was previously suggested, one could make sure that the 'C' solenoid matches the TCU, regardless of original configuration.

Charl

[oab_au]

Thanks for all your searching Phil. Puts that worry to rest.

Harvey.

[NeedForSpeed]

Phil, the Master at work again, bravo!

[oab_au]

I thought you might be interested, Ron, late box early TCU.

Harvey.

[NeedForSpeed]

Phil confirms what you discovered via part numbers and experience, exactly what I confirmed with US part numbers and my experience. There can be no doubt about the differences now.

Originally Posted by oab_au

I thought you might be interested, Ron, late box early TCU.

Harvey.

[svxistentialist]

Thank you gentlemen.

Result!!