5EAT TCU Reverse Engineering

[KyLegacy 2.5GT]

The increase in line pressure will result in a stronger, more crisp shift... but it will most likely not make the shifts much faster. This increase will also allow the clutch packs to hold more power.... how much more????... I don't know. As utc says, you would need to drill out some of the holes in the valve body and place stiffer springs in there to decrease shift time. Fluid can only flow so fast through a given orifice. The larger hole will allow more hydraulic fluid to reach and fill the final port faster.

 

From reading online, it looks like a lot of the Chevy LS guys are using an aftermarket program, much like RomRaider (called HP Tuners), to bump up their line pressure without using a shift kit. They all seem to like the modification.

 

I still would like to try out the 350Z shift kit... maybe after I buy a house next year .

[KyLegacy 2.5GT]

Oh yeah, by the way, increasing the line pressure will cause less slip in the clutches and make them last much longer!

[ClimberDHexMods]

Can't wait to get around to messing with the line pressure!!!

 

BTW there are lots of modified valve bodies for sale now, so the opportunity is ripe. IPT may add a zero to what would be a fair price, but their used VBs do the job.

[NSFW]

I really want to understand the posts above, but it's still a bit martian to me. If I get a few free hours someday, I may be able to begin to get it.

 

That stuff was basically just me thinking out loud while I tried to figure out how to make use of the information in the thread that utc_pyro referred to. What I wrote there will make more sense if you read about the SSM protocol first.

 

This document describes the sequences of bytes that the SSM tools (including RomRaider) send to the ECU, and the responses that come back from the ECU.

 

http://www.romraider.com/RomRaider/SsmProtocol

 

This is pretty low-level stuff. It may or may not be a worthwhile investment of your time. It couldn't hurt to get a rough idea of how it all works though.

[subarutech77]

I was able to get a look at my wife's 05 obxt today with the ssm3. The cal id of her TCM is: MB436G

 

And the cal id of the reflash is MB436M

 

So it looks like I could reflash the TCM. I haven't done it yet, and not sure it would help the cause without some sort of monitoring device when it's being reflashed

 

Otherwise, what else would be helpful?

 

A datasheet for the processor chip? That would tell you what the pads are for to use a debugger? And/or the correct init command and address in the TCM to be able to talk to the TCM? Possibly you've made some progress over at RR?

[utc_pyro]

To reprogram it, we need the data sheet of the processor (or a least a good idea of what it is). That way we'd know what to expect code wise and thus how to disesembe it. It may help to decode those programing pads, may not, but it should help.

 

After we figure that out, sniffing the SSM3 flashing the TCM could tell us HOW the rom is loaded onto the TCM. We can supply that info to Coby at Tactrix for ECU flash support of it, allowing us to flash our new versions down the road.

 

After that, we load up IDA (if it works with said core) and start figuring out how the thing thinks and how to change it's mind .

 

For now getting logging support, we need to figure out how the TCM talks via SSM (if it even does). Thus wen need to develop the deffinitions for it and get the direct SSM address. Thus the work over on RomRaider doing a "port scan" on the K-Line.

[underground000]

Bump, anyone tried the resistor mod?? Im away from my car for another 2 weeks:mad:

 

Heres a link to a guy selling the resistor on eBay, or Im sure you can try an audio shop

[dschultz]

Has anyone tried this software out on their AT car?

[RIPjeep2002]

^^interesting....

[utc_pyro]

Does not work with my OpenPort 2.0.... Some one with a 1.3 or vag-com cable want to try?

 

It does not mention the 5eat being supported, but we can take a peak at the source to see how the TCU talks.

 

I think we can at least make logging definitions for RomRaider, and probably edit his files to work with the 5eat. It looks like it's all in C. SSMprotocol2_def_en.cpp is good

 

Were did you find that?

 

edit: Just ordered a VAG-COM cable .

Edited September 2, 2010 by utc_pyro

[ClimberDHexMods]

I took a look at the valve body. there is nothing to indicate a certain kind of chip. Once I get back from my honeymoon I can perhaps risk taking it apart and seeing if I can put it back together without bricking it. And getting more pics for you. Perhaps. Turns out it's easy to take apart. I just don't know anything about it except what it does and generally how.

[underground000]

Did you buy the 350z shift kit or planning of buying it after you experiment w/ the VB?

[utc_pyro]

I took a look at the valve body. there is nothing to indicate a certain kind of chip. Once I get back from my honeymoon I can perhaps risk taking it apart and seeing if I can put it back together without bricking it. And getting more pics for you. Perhaps. Turns out it's easy to take apart. I just don't know anything about it except what it does and generally how.

 

That black box in the middle is what we need for the electronics side. Should be fairly easy to crack open. For the Hydraulic side, we need the rest . (replying to post in other thread) It's probably best if you keep the valve body, as I wont have any way to trace the Hydraulic lines into the transmission to see where they go.

 

If there looks to be hope on messing with the stuff in the black box (need high-res pic of circuit board), you can send that to me to fiddle with. I'll send it back after I'm finished or can't get any where with it.

 

Congrats on getting married!

Edited September 2, 2010 by utc_pyro

[ClimberDHexMods]

Re Nissan 5eat shift kit. It's low on the list of things for me to get into because I have a LONG list, and I already have a VB modified by IPT, installed. It is nice but could still shift quicker!!! The time may eventually come. Honestly I would try to turn it into a small side business, and a couple folks would have to be willing to get behind me and send me VBs to modify once/if confirmed successful in order for me to get into it or I would effectively be making a replica of the VB I already have. I have no use for two of the same thing. Just trying to be realistic.

 

That black box in the middle is what we need for the electronics side. Should be fairly easy to crack open. For the Hydraulic side, we need the rest . (replying to post in other thread) It's probably best if you keep the valve body, as I wont have any way to trace the Hydraulic lines into the transmission to see where they go.

 

If there looks to be hope on messing with the stuff in the black box (need high-res pic of circuit board), you can send that to me to fiddle with. I'll send it back after I'm finished or can't get any where with it.

 

Congrats on getting married!

 

When I get back I'll see if I can't get that board off. Sounds like you won't destroy it Jatco conveniently used harnesses with connectors on it, so shouldn't be too terribly hard to remove (hopefully!)

 

Also, the 5eat manual outlines what parts of the trans get activated during each process the 5eat performs. If there is any way I would not need to tear open the main case of the 5eat, that would be best. It's seriously an endless and complicated maze in there and I would surely screw it up. Some people far more experienced than me won't touch these things. The local American trans guy wouldn't even touch it, and he only does transmissions. There has to be an easier way than me going inside to follow passage ways.

Edited September 2, 2010 by ClimberD@HexMods

[dschultz]

Does not work with my OpenPort 2.0.... Some one with a 1.3 or vag-com cable want to try?

 

Were did you find that?

 

edit: Just ordered a VAG-COM cable .

Found just by poking around on the InterWeb...

 

It works with my VAG-COM, but I don't have a TCU (other than my left foot and right hand )

[hadvw]

Found just by poking around on the InterWeb...

 

It works with my VAG-COM, but I don't have a TCU (other than my left foot and right hand )

 

Hmm. I have a TCU, and a cheap VAG-COM cable I bought off Ebay..

 

If only I had spare time..

[Leonardo]

Slacker!

[utc_pyro]

Hmm. I have a TCU, and a cheap VAG-COM cable I bought off Ebay..

 

If only I had spare time..

 

Get on it man! I think we need to modify it a little to work with the 5eat, but you can be a beta tester .

 

We have more clutches then they have, and these settings are NOT in the SSMIII. Thus we may be a little blind here unless the Dev wants to support us.

[hadvw]

Get on it man! I think we need to modify it a little to work with the 5eat, but you can be a beta tester .

 

We have more clutches then they have, and these settings are NOT in the SSMIII. Thus we may be a little blind here unless the Dev wants to support us.

 

Well, you could be a beta tester too :-)

 

Honestly, I've been working overtime for the past few weeks, and it's starting to affect me. I plugged in a used power adapter I bought to power our exercise bike without testing it (I know, I should have), and while it SAID 6v, it was putting out 10+V and burned out the circuit board on the bike. So, that's $100+ down the drain for trying to save $5.

 

No, not the end of the world, but I REALLY can't afford to do this kind of beta testing on my car (needed as a DD) and mess anything up.. With the stress and lack of "down" time I've had lately, I really don't trust myself to do anything but hook it up and see what options it shows...

[RIPjeep2002]

^^Even if you hook it up and see what the data shows, it is a starting point for other people to go off of.

[65comet]

I called TransGo about a shift kit for the 5EAT. They said they would do it for $350 and would like the valve body for a week or two. Sounds like they want to make a custom kit, but need a valve body to create it. They said that the Suby 5EAT valvebody should be close to the kit needed for the 350Z - part #RE5RO5A-HD2.

 

http://www.transgo.com/rpg_nissan.php

 

I could hear the TransGo folks talking it over in the background. They came back and said that the 350Z kit was complicated and they had several people have trouble installing the kit. They did not recommend anyone but an experience professional installing that particular shift kit.

 

Looking at diagrams of the kit on the web, it did not look overly complicated however.

[utc_pyro]

Well, you could be a beta tester too :-)

 

Heh, I'm planing on it (for this one at least). I just have to wait for my cable to get here....

 

Like RIPjeep2002 said, if you can at least hook up and see if it talks it would be helpful.

[lieutenantcolumbo]

As far as I know, I am the only one running a TransGo kit in the 5EAT. Look at the 5EAT Pride thread.

 

My transmission installer said this is nothing that should be attempted by anybody who doesn't have years of transmission experience (he has +25 years).

 

Furthermore he works with TransGo to test their parts. What he put in my car was not just a standard 350z kit, but it was the basis for the upgrade. He said TransGo swapped out some parts, and I guess the holes they drill might be slightly different. He did other things too when they rebuilt my transmission like adding extra clutches for both fourth and fifth gears, welding the torque convertor, added some stainless steel parts (can't remember what exactly), and I am sure I left out some stuff as well. Don't think they did anything with the resistor mod, but I could be wrong.

 

Its been running great now for several months and several thousand miles. Overall I am very pleased so far.

[Mortal2None]

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[KyLegacy 2.5GT]

I am going to try this program out tonight with my buddies laptop.... I have Windows 7 64 bit on my laptop and it seems as though it only works on 32 bit. I will report back and let you know.