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2008 JDM Outback 3.0R, 5EAT
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Did anyone try the TCU adjustment in FreeSSM "Correction of AWD Clutch Torque" ? Curious to know what this is if anyone knows or has tested it. It's not mentioned in the SSM-III manual although from this GitHub discussion with the FreeSSM developer if it's listed as an adjustment on FreeSSM then it is a hidden TCU feature for Subaru technicians to use.
 

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@ntippet did. See post #1 in FreeSSM - Complete access to your ECM and TCU. However, that was on a 4AT. The 5AT might not have this available because the planetary center differential provides full time AWD. The 4AT MPT clutch system, which depends solely on the clutch engagement for AWD, might be more "needy" in regard to the clutch pressure level and, therefore the functional adjustment.

Are you working on the further development of FreeSSM?
 

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2008 JDM Outback 3.0R, 5EAT
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Are you working on the further development of FreeSSM?
I'm not writing FreeSSM source code but have compiled the app to test Tactrix OpenPort 2.0 support and the adjustment value described above. Our Subaru community is fortunate that FreeSSM developer Comer352 maintains his open-source product to a high standard and is responsive to comments and questions on GitHub. I guess my interest is my car always seems to 'drive heavy' and I was just curious to take a look at the drive-train adjustment values listed on FreeSSM. Strangely a month or so back the car drove amazingly just for one trip, cruising effortlessly with surreal acceleration. Next day it was back to the usual feel of towing a cement mixer! I don't expect the FreeSSM adjustment values to address this anomaly but am always interested when there's a feature to explore

@ntippet did. See post #1. However, that was on a 4AT. The 5AT might not have this available because the planetary center differential provides full time AWD. The 4AT MPT clutch system, which depends solely on the clutch engagement for AWD, might be more "needy" in regard to the clutch pressure level and, therefore the functional adjustment.
The adjustment ntippet made was "Correction of Transfer Duty ratio" on his 4EAT which may be related to the adjustment parameter reported on the 5EAT "Correction of AWD Clutch Torque". Yesterday I was able to change this value from 0Nm to 2Nm to test that the TCU accepted a new value but haven't had a chance to test drive and will then revert back to the default of 0Nm. My simple understanding is that the 5EAT TCU controls the transfer clutch based on many inputs including front and rear wheel speed to adjust available power to the centre diff and therefore rear diff and rear wheels with more power to the back during acceleration or slipping and less whilst cruising or braking.
 

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01 VDC, 05 R Sedan, 06 BAJA EJ257
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I believe the TCM will also turn the clutch off during heavy braking, down hill braking, down hill coasting and any time you are WOT. I will have to find the article again, but it is similar in function to the VTD in the 4EAT.
 

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My simple understanding is that the 5EAT TCU controls the transfer clutch based on many inputs including front and rear wheel speed to adjust available power to the centre diff and therefore rear diff
The 5EAT, unlike the 4AT, does not use a transfer clutch to convey power to the rear in normal driving. The 5EAT has a mechanical (gear set) differential in the tail section of the transmission. This sends power to the front and rear at all times, the same as the front and rear differentials themselves send torque to their two respective wheels all the time. There's no way to disegage the rear drive, e.g., make the car FWD.

In contrast, if the transfer clutch in the 4EAT is disengaged by setting the transfer clutch drive signal accordingly, no torque is applied to the rear drive; the car is FWD.

Similarly, the 4EAT has an AWD fuse socket. When a fuse in installed in the socket, the transfer clutch is disengaged. The 5EAT doesn't have this, and that's because there's no way to remotely disable the mechanical differential's function of distributing torque to the front and rear drives.

Unlike the 4EAT, the clutch in the 5EAT need not be engaged except if there's slippage, or a risk of slippage (e.g., rapid acceleration from a stop). Consequently, the way the TCM controls the 5EAT clutch is different than it is in the 4EAT. The 5EAT clutch is needed only to prevent slippage, not to maintain AWD in normal conditions.

In the first post of the FreeSSM thread, ntippet notes that the 4EAT adjustment was made to reduce the possibility of torque bind in slow speed cornering; it's just backing off the clutch engagement a bit to allow the clutch plates to slip more easily during the turns. The clutch is still engaged, at least partially.

But, as the clutch in the 5EAT is not needed to provide the ongoing all-wheel-drive, it can be relaxed most of the time. Consequently, the same adjustment that might be needed in the 4EAT to "trim" the clutch engagement, might not be relevant to the 5EAT.

I believe the TCM will also turn the clutch off during heavy braking, down hill braking, down hill coasting and any time you are WOT. I will have to find the article again, but it is similar in function to the VTD in the 4EAT.
In the 4EAT with the MPT clutch (also in the CVT), the clutch is always engaged to some degree. This is evident from the observations in the FreeSSM thread and my own logs. The transfer solenoid duty cycle does not drop below 30% when in a drive gear; the clutch is always engaged to some degree.
 

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01 VDC, 05 R Sedan, 06 BAJA EJ257
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@plain OM
I was referring to the VTD center diff attached to the 4EAT in the VDC models. The way the diff is managed is the same. 😁
 

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2008 JDM Outback 3.0R, 5EAT
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Just my close out on adjustment value "Correction of AWD Clutch Torque" in FreeSSM. My 5EAT transmission accepted a range for this adjustment value of 0-5Nm with other values rejected by the TCU. With this value set to 2Nm and on the road there seems to be more of a push from the drive train whilst cruising so I can confirm that it does have an effect. I've reset it back to 0Nm so an interesting experience albeit not necessary for daily driving or other troubleshooting at this stage. I did have to compile the FreeSSM master (dev) code branch to use this feature with Tactrix Openport and found instructions on this page. Interestingly the SSM2 measuring block and adjustment titles displayed in FreeSSM are defined in the ECU or TCU and sent to FreeSSM for display and access.

505321
 

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(formerly) 03 H6 OBW , (presently) 06 WRX Sportwagon & 2021 Honda CR-V
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Just my close out on adjustment value "Correction of AWD Clutch Torque" in FreeSSM. My 5EAT transmission accepted a range for this adjustment value of 0-5Nm with other values rejected by the TCU. With this value set to 2Nm and on the road there seems to be more of a push from the drive train whilst cruising so I can confirm that it does have an effect. I've reset it back to 0Nm so an interesting experience albeit not necessary for daily driving or other troubleshooting at this stage. I did have to compile the FreeSSM master (dev) code branch to use this feature with Tactrix Openport and found instructions on this page. Interestingly the SSM2 measuring block and adjustment titles displayed in FreeSSM are defined in the ECU or TCU and sent to FreeSSM for display and access.

View attachment 505321

would this be helpful for someone who 'primarily' was towing, or, offroad?
 

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Yes, FreeSSM and Romraider work with Windows 10; however, I don't know if either can access the transmission control module to look at the secondary pressure problem that you posted in: CVT Fluid pressure sensor

I suggest looking through this thread to see if anyone has reported either program working with the CVT and displaying that parameter.

Here's one post that shows limited coverage in a 2012 CVT: Post with some CVT parameters
 

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Yes, FreeSSM and Romraider work with Windows 10; however, I don't know if either can access the transmission control module to look at the secondary pressure problem that you posted in: CVT Fluid pressure sensor

I suggest looking through this thread to see if anyone has reported either program working with the CVT and displaying that parameter.

Here's one post that shows limited coverage in a 2012 CVT: Post with some CVT parameters
Finaly, I try the software on Windows Xp and I use the cable recommanded. I can access to the Engine Control Unit but I can't access to the Transmission Control Unit.
 

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2009 Tribeca Now - 2004 Outback EJ259 - Sold
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Discussion Starter · #1,092 ·
The thread still lives!
Hah.
 

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Coming from the world of BMW. We had access to a program that allowed us to do some adjustments to certain parameters. The only thing I'm interested in doing is converting my turn signal and other bulbs to LED. There was a place you could do that to ensure that the lights did not flash fast. BMW also had a system that did hot and cold checks on the lights. If you had LED lights installed where a halogen was before you would get a flicker. I'm just trying to avoid that.

Thanks in advance for all the help!!

I have a 2021 Limited XT Outback if that helps.
 

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As far as I know, neither FreeSSM nor Romraider will connect to the modules in a 2021. (Although I understand that FreeSSM might be under further development, so something could eventually come from that.) At this point, if there's any tool that can make the mods of interest, I suspect it's the dealer Subaru Select Monitor IV (or perhaps it's now version V).
 

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Hello,

Connected it to my Impreza 4EAT. It recognizes my transmission, but no adjustments are available, table is blank.

I have cleared memory 2 and it seemed to shift smoother for several minutes, but then got back to rough again.
How do I do a proper relearn?

ROM ID D2E5603000
Also having problems with an 07 Impreza 2.5I 4EAT
 

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I am having the same issue with my 07 Impreza 2.5I. Anyone know why it doesn't show transmission adjustments?
I suppose the "it" is FreeSSM. (This thread also discusses Romraider, which is a different program, not to be confused with FreeSSM .)

I believe the adjustments were available only with the earlier generation of the 4AT transmission. I don't recall seeing any adjustments for my 07 4AT, but it's been a long time since I've used FreeSSM for transmission data.
 

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Very possible. @ntippet , however, in post #1 here, shows the available 4AT "Adjustments" in the 2004 that was being used to test the FreeSSM programs usefulness in monitoring, and later Romraider for it's logging capability (although Romraider never had "adjustments" functionality). I guess some do, some don't.
 

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2008 JDM Outback 3.0R, 5EAT
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If we look through the FreeSSM code it's the ECU and TCU that tell FreeSSM which parameters or adjustments are available once the connections are made. Hence if a parameter or adjustment is not shown it's because the car doesn't support it. The tests are slightly different as FreeSSM has to know more to conduct them so may be listed but are not available for all vehicles.
 
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