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5EAT TCU Reverse Engineering


utc_pyro

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Ive got a question i seen utc's post on changing requested torque tables is that something i can mention to my tuner or does he have to do some research?

 

You want the calculated torque to roughly match what the motor is actually putting out, so they'd need to model that. The units are suspiciously close to Newton-Meters. The three tuners I listed above (especially the one posting in this thread) have already developed "maps" for this, but your tuner could also make one.

 

If you use a Accessport, you're SOL.

 

Do i even need to do that since ive got the f1?

 

Yes. Especially if you've changed the injectors, and if you're stage 3 I presume you have.

 

Also will that change the lag from manual shifting?

 

No, that has to do with other issues that haven't been identified yet. A guy over on Romraider was already looking for that in the JDM TCU code, and couldn't find any sort of delay counter. The shift buttons are wired up to BIU so the delay may actually be in there.

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You want the calculated torque to roughly match what the motor is actually putting out, so they'd need to model that. The units are suspiciously close to Newton-Meters. The three tuners I listed above (especially the one posting in this thread) have already developed "maps" for this, but your tuner could also make one.

 

If you use a Accessport, you're SOL.

 

 

 

Yes. Especially if you've changed the injectors, and if you're stage 3 I presume you have.

 

 

 

No, that has to do with other issues that haven't been identified yet. A guy over on Romraider was already looking for that in the JDM TCU code, and couldn't find any sort of delay counter. The shift buttons are wired up to BIU so the delay may actually be in there.

 

man that sucks that a popular tuning company doesnt support that. Well I hope Rev Works support open source tuning then. The tuner there is known for opening a very good tuna with no crust

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Ive got a question i seen utc's post on changing requested torque tables is that something i can mention to my tuner or does he have to do some research? Do i even need to do that since ive got the f1? Also will that change the lag from manual shifting?

 

You would need some type of hydraulically actuated paddle system to get the instashift that everyone expects from manual mode. These will never shift like a formula one car.

 

If you use a Accessport, you're SOL.

 

Are you sure?

 

There are RT monitors in newton metres on my AP. As far as I know, accessport tuners are able to manipulate these tables as well.

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You would need some type of hydraulically actuated paddle system to get the instashift that everyone expects from manual mode. These will never shift like a formula one car.

 

You know the BIU has a delay counter to see if you're trying to change multiple gears at once right? Based on what're been found so far that's the likely delay spot. When the TCU decides to shift, it can do so extreamly quickly. I need to post a video of what my car does now, it shifts faster than my buddies S3 that has a DSG.

 

After this is confirmed in the TCU code one could make a canbus module to simulate the BIU but not have the delay.

 

 

Are you sure?

 

There are RT monitors in newton metres on my AP. As far as I know, accessport tuners are able to manipulate these tables as well.

 

The RT tables actually don't matter as much. The CALCUALTED TORQUE tables are the real deal in changing how things feel. They don't have that table defines in Romraider. ECUtec does though.

 

Even worse: on the '05-'06 cars this table is based on injector pulse width. If you change the injectors without tweaking this, the transmission thinks the motor is putting out LESS powered and reduces line pressure and burnes out faster.

Edited by utc_pyro
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The RT tables actually don't matter as much. The CALCUALTED TORQUE tables are the real deal in changing how things feel. They don't have that table defines in Romraider. ECUtec does though.

 

Is there someplace where I can read about the calculated tables? For example, what are the X and Y axes (both "what do they mean" and "what is the range of values"), and what is the range of values within the table?

 

Knowing how they would work might help me find them... I have an 05 OBXT now, with a 5EAT, and I'm willing to spend some time digging for these tables. But I need to know where to start digging.

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Is there someplace where I can read about the calculated tables? For example, what are the X and Y axes (both "what do they mean" and "what is the range of values"), and what is the range of values within the table?

 

Knowing how they would work might help me find them... I have an 05 OBXT now, with a 5EAT, and I'm willing to spend some time digging for these tables. But I need to know where to start digging.

 

What year?

 

Edit: missed the '05 part. Will post the location of the table later so you can start digging into it.

Edited by utc_pyro
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Is there someplace where I can read about the calculated tables? For example, what are the X and Y axes (both "what do they mean" and "what is the range of values"), and what is the range of values within the table?

 

 

 

Knowing how they would work might help me find them... I have an 05 OBXT now, with a 5EAT, and I'm willing to spend some time digging for these tables. But I need to know where to start digging.

 

 

 

Of course there's a long thread over on RR.com about this.

 

Earlier cars use rpm and IPW for axes. Later ones use rpm vs. load in g/rev. The values in stock ROMs are suspiciously close to what torque output might be in Nm. What we do know about the output data is that it's one of the few things the ECU passes to the TCU. It also seems the VDC system evaluates it for adapting system response. Maximum values vary by year. I've come across ROMs that would accept no more than a raw value of IIRC 440, while others will take a full 512.

Edited by fahr_side
Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs.
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NSFW, take a look at the 5EAT Ask You're Questions starting around page 85. I think this post has your table address.

 

 

So far I've checked this with A2WC521R, A2WC521C and A2WF200C. If you have another '05-'06 ROM let me know and I'll look. It's pretty easy to find in ScoobyRom, just look for the table who's X-Axis maxes out at 13000

 

<table name="Calc Engine Torque" category="UTC_Pyro Beta" address="c164c" type="3D" level="1" scaling="RequestedTorque(rawecuvalue)">
<description>Calculated Crank Engine Torque relative to [Load (G/rev) * (RAW) Injector scaling] vs RPM.</description>
<table name="Engine Load" address="c15dc" type="X Axis" elements="13" scaling="g/rev"/>
<table name="Engine Speed" address="c1610" type="Y Axis" elements="15" scaling="RPM"/>
</table>

 

A little bird said you can bump the value to to 415, but I have not verified that myself. Car has been in the shop for two weeks with no sign of coming out any time soon.

 

Additionally as fahr_side stated there are a few good threads on romraider. Start here: http://www.romraider.com/forum/viewtopic.php?f=40&t=9358

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You know the BIU has a delay counter to see if you're trying to change multiple gears at once right? Based on what're been found so far that's the likely delay spot. When the TCU decides to shift, it can do so extreamly quickly. I need to post a video of what my car does now, it shifts faster than my buddies S3

 

I really did'nt get much from the 5EAT tuning videos. Would certainly be interested in knowing your trans mods and seeing the video, sounds like you're onto something here. If it can shift faster (on command) than a dsg, I'm sold. But again, how much work does it take to dial this in? I don't know if it would be worth the risk to run an "off the shelf" transmission map.

Edited by The 2Fiver
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I really did'nt get much from the 5EAT tuning videos. Would certainly be interested in knowing your trans mods and seeing the video, sounds like you're onto something here. If it can shift faster (on command) than a dsg, I'm sold. But again, how much work does it take to dial this in? I don't know if it would be worth the risk to run an "off the shelf" transmission map.

 

I think what utc_pyro is saying that, with the Hexmods F1 (which I have as well), that once a shift starts, it finishes VERY quickly, depending on load, etc. If you're at WOT in sport-auto mode, it can really bang off the shifts.

 

However, in manual mode, there is sometimes still a delay in shifting. It doesn't feel instantaneous. This delay between "user presses shift" and "TCU decides to shift" is still somewhat a mystery. The current theory is that the TCU can shift very quickly when it wants to, especially with an F1. However, no one knows exactly where/when the decision is made to shift, and why it can take 1-2 seconds from "please shift" to "ok, I need to shift". It may be a BIU delay, waiting for multiple presses, or it may be something in the TCU code, which is why the hope is that the ROM may give some more clues..

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Exactally what hadvw said. The button press to when the TCU decides the shift hasn't changed. What has changed is how the shift goes down once it decides to. They are rip the drivetrain out rally car quick now.

 

This is with a Transgo shift kit (similar to the F1) and the calculated torque tables messed with. I've tried just scaling the CT table up, and two tables from tuners. The one that kind of matched the actual output of the motor had the best subjective feel.

 

The RT tables seem to have more of an effect on shift point than sharpness of the shifting. I'm running a kind of linear tables based on NSFW's, and while that has changed the shift points it hasn't really changed the shift speed.

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Just a curiosity, has anyone opened up a BIU to see how the circuity is? Since now you guys have mentioned that the delay might be in either the TCU or the BIU or both, im curious if the delay is in the BIU

 

Edit: Is the BIU part of the alarm or is it the alarm system?

Edited by nightfire37
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It is the alarm system. Along with being the CANBUS hub, lighting controller (depending on year), door lock controller, defroster controller, and a few other random things. Any delay in that guy would probably be software related, and there aren't a lot of people out there with the skill set to reverse engineer 15+ year old proprietary japanese microcontrollers.
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Not sure if you were understanding what I mean but opened the BIU and taken any pictures related to the board and looked up the chips. I might want to open mine and look at the board to see what chips it is if it helps
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I think what utc_pyro is saying that, with the Hexmods F1 (which I have as well), that once a shift starts, it finishes VERY quickly, depending on load, etc. If you're at WOT in sport-auto mode, it can really bang off the shifts.

 

Was implying that the manual paddle/switch flip coupled with a fast ship would be ideal. I've seen the trans-go videos, tough to tell if it actually shifts faster than my own car.

 

I've tried just scaling the CT table up, and two tables from tuners. The one that kind of matched the actual output of the motor had the best subjective feel.

 

^might just come down to that too.

 

 

Do you guys ever run datalogs during your shift operations and review it?

Would that be an accurate way of determining how quickly the transmission grabs under WOT? Also, does 5eat tuning pay any mind to daily driving duties in auto mode?

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Exactally what hadvw said. The button press to when the TCU decides the shift hasn't changed. What has changed is how the shift goes down once it decides to. They are rip the drivetrain out rally car quick now.

Yes, it's not the shift that is slow, it seems to be the TCU making up it's mind if it wants to or not.

This is with a Transgo shift kit (similar to the F1) and the calculated torque tables messed with. I've tried just scaling the CT table up, and two tables from tuners. The one that kind of matched the actual output of the motor had the best subjective feel.

Yes, to a point. Of course the closer the CT to TCU is to the actual torque output the more it will feel like it would have stock, if the car came with those mods from the factory. That's not to say you can't further improve shift feel or consistency with more tweaking however. You definitely can go too high with the CT values and get into some unpleasant behavior.

The RT tables seem to have more of an effect on shift point than sharpness of the shifting. I'm running a kind of linear tables based on NSFW's, and while that has changed the shift points it hasn't really changed the shift speed.

Pretty much. Raising RT does raise the rpm at which the trans will shift and it can be quite finicky, with a change of even 10 units making shifts 100s of rpm higher or lower. I think the shift feel may change simply because the higher the rpm the trans shifts at the higher line pressure seems to be. I don't think the RT value changes line pressure in and of itself.

 

Really looking forward to seeing the logic laid out.

Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs.
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When I logged the canbus message from the BIU the car was in the garage and the message was instant. Holding the paddle sent multiple messages.

 

As soon as I have time I will log the same thing on the road.

I will also try to send a shift message from my computer.

 

I found the calculated torque table in my rom yesterday. Anynone has any input on what values to try? I have a 2005 JDM with vf37, fmic, 3" and a Transgo kit.

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^might just come down to that too.

 

 

Do you guys ever run datalogs during your shift operations and review it?

Would that be an accurate way of determining how quickly the transmission grabs under WOT? Also, does 5eat tuning pay any mind to daily driving duties in auto mode?

 

That was my original plan, but I ended up changing too many variables at once to get a valid before and after :redface:.

 

I'll dig through some logs tonight to see what the shift speed actually is, then you could compare that to your logs.

 

When I logged the canbus message from the BIU the car was in the garage and the message was instant. Holding the paddle sent multiple messages.

 

As soon as I have time I will log the same thing on the road.

I will also try to send a shift message from my computer.

 

Sounds like any presumptions of if something is in the TCU or not was too early.

 

What are you using to log and send canbus messages out of curiosity?

Edited by utc_pyro
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Yes it is. I havent found the can message in the tcu rom yet.

 

http://www.fischl.de/usbtin/

 

Cool - looks like a CAN-bus sniffer. But it also seems to have an "active" mode? Does that mean you could SEND CAN-bus commands?

 

If so, rig up a button to send a shift command, see how fast the TCU responds..

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Cool - looks like a CAN-bus sniffer. But it also seems to have an "active" mode? Does that mean you could SEND CAN-bus commands?

 

If so, rig up a button to send a shift command, see how fast the TCU responds..

 

I will

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Cool - looks like a CAN-bus sniffer. But it also seems to have an "active" mode? Does that mean you could SEND CAN-bus commands?

 

If so, rig up a button to send a shift command, see how fast the TCU responds..

 

I have a bluetooth obd reader with capability of sniffing the can system. Will try with one of my family's newer vehicles first to see then i will try on mine. Do you think the car needs to run to see any data or no? its right now out of commission where I cannot turn or drive the vehicle cause i need to rebuild the engine:spin:

 

Edit: I tried with what I have and nothing is working. I have this exact OBD Reader I have with a Raspberry Pi 3 and my Windows 10 laptop. Anyone know of any free software to read any CAN bus codes?

Edited by nightfire37
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I have a bluetooth obd reader with capability of sniffing the can system. Will try with one of my family's newer vehicles first to see then i will try on mine. Do you think the car needs to run to see any data or no? its right now out of commission where I cannot turn or drive the vehicle cause i need to rebuild the engine:spin:

 

Edit: I tried with what I have and nothing is working. I have this exact OBD Reader I have with a Raspberry Pi 3 and my Windows 10 laptop. Anyone know of any free software to read any CAN bus codes?

 

Ignition on and the canmessages will start.

Maybe it will work with socketcan?

 

In my 2005 the canbus wires are not connected to the obd2 port.

Edited by roadie08
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Did some more canbus logging today.

 

D mode upshift starts with 51482

Sport mode upshift starts with 51483

 

Engine on D mode

t51482000730048931500

t51482000730048931700

t51482000730008921900

t51482000730008921B00

t51482000730048911D00

t51482000730048911F00

t51482000730088911100

 

Driving slow in D mode

t514820007300C8A41D00

t514820007300C8A41F00

t51482000730088A31100

t51482000730088A31300

t51482000730008A31500

t51482000730008A31700

t51482000720088A81B00

t514820007200C8A31D00

 

WOT in Sport mode

t514830006F0008EB1300

t514830006F0008EC1500

t514830006F0008EC1700

t514830006F0048EA1900

t514830006F0048EA1B00

t514830006F0088EA1D00

t514830006F0088EA1F00

t514830006F0048D21B00

t514830006F0008D41D00

t514830006F0088CD1100

 

I copied one message and changed some of the last digits. It shifts at the same speed, but it was a copied message and I dont know what the last bytes is. Looks like some kind of timestamp but dont know if it is something more than that. I could only use one message for one shift then I had to change some digit.

 

So back to the disassembly of the TCU. Anynone had any luck?

Edited by roadie08
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