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Those could be failsafe values in case of a pressure sensor loss. Very smart of bmw if so, they must've implemented some pressure control logic as well if in fact they've a pressure sensor failsafe routine.
 

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Discussion Starter #22
Maybe there are failsafe values, but there is a time and place to display them. My point is that a diag tool that proports to show “Analogue Values” isn’t that place, especially when no sensors are hooked up. Diag tools should show the state values, which in German are the ISWERT.

I also know that if the pressure sensor is unplugged the pump will just keep running so it’s in open loop operation which is one way to get the pump to turn on, but you can’t use that to shut off the pump. So there’s no runaway failsafe aside from the motor possibly triggering the fuse from excessive load or some blow off valve that I’ve not encountered.
 

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The SMG pdf hydraulic diagram shows a pressure relief valve. If the pump run time protections are disabled when the pressure sensor is unplugged then it's definitely a failsafe implementation.

INPA is not meant for public distribution, so engineers using it better know what it's showing.
 

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Discussion Starter #24
Right, so there is a relief valve, that’s reassuring. But I’m not sure why you believe that 70 bar pressure value with nothing hooked up represents failsafe value vs something else. If you do know something about that it would be nice if you shared that.

Do you know what INPA is showing in these or other instances? I’ve been in many situations where I or other engineers can’t figure out what the data shows because it doesn’t match the real world observations. I also have seen a lot of buggy software too. I don’t expect INPA to be perfect but if you know that something is wrong or unreliable it would be nice to know since BMW want everyone to just replace the whole hydro unit for 8k. I’m sure this will be 10k next year.
 

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Discussion Starter #25
Actuator block was replaced with it’s corresponding gear strip sensor. After a lot of bleeding it seems that trans adapt routine works fine.

For some much needed R&D, I also then installed the non matched gear position sensor strip (the one I repaired) to the actuator block and that
resulted in failure to adapt the trans. This was after 2 hrs of bleeding, because the 2 range solenoids need to be removed and that opens up the hydraulics again. As a result of this experiment, I’m concluding that my 1) repair was bad or not enough OR/AND 2)that it validates what Jim Colley mentioned about gear strip sensors not being interchangeable with other actuator blocks.

If my repair was “known good”, that would reinforce the latter, #2 since the former #1 would not have been a possible contributing factor. My research seems to surface that Jim only seemed to mention some issues when attempting to swap sensors but nothing specific to the errors or failure modes one wouldee (failure to adapt at the very end of the adaption sequence).
Commanding gears in INPA and ISTA never were a problem, all sound very solid like the videos I mentioned, the gears are always displayed on the screen and dash, which people reading this need to understand is basically useless in determining if the gear strip sensor works. As I mentioned in post 15, after Platii’s video, these tests are open loop test routines and say nothing about the health or operation of the gear strip sensor or it’s wiring.

So all that is left is clutch-slip adaptation after i reinstall the driveshaft, however I may have other issues, since this trans has 127k miles and I don’t know about the PCLD and clutch control solenoid, which are original. I have another one if each that are used but seem to be from 2015 like my actuator block. The driveshaft will be hooked up this time, but still a bit doubtful if that was the cause of the issues of input speed not reaching zero.
 

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I just saw your last post.
Have you gotten any values recorded since you swapped the gear position sensor, I would have love to see those values with Inpa manual command, in which adaptation test the swapped sensor failed. For the slip pint test failure, have you tried to stop the output shaft by any mean or install the driveshaft?. In fact it does make sense that the ECU is confused, the transmission is suppose to be zeo in Neutral and for that test the ideal speed is zero, but he is sensing a rotation.
I would scroll to the page where it shows the transmission speed and observe the speed if it is counting or zero to confirm the theory and the reason for the failure. (drive shaft not installed).
 

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Discussion Starter #27
I decided to also replace the clutch fork although the old one seemed fine, especially when I compared the two. Also the PCLD. I hooked up the drive shaft and it adapted fine. Not going to try hooking up the output shaft to anything else, that’s dangerous and silly from my point of view. Maybe next week the other parts will come and and I will drive it and then we’ll see about cogs and other silliness.

I never had any problem commanding gears with INPA or ISTA with either strip sensor. It won’t adapt complete trans with the one I tried to repair and also not with the sensor when it’s not matched to the original block.
 

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Great, so you solved the slip point adaptation with installing the driveshaft to stop the output shaft from rotation, which made sense. What step failed the complete transmission adaptation with the sensor you repaired installed?. (Trying to figure out whats wrong with the sensor, or may be the block is bad), did you install another block with it's sensor?.
 

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Discussion Starter #29
No that’s not necessarily true solution. I also replaced PCLD and clutch fork. Those were originally not replaced. I don’t believe it was the clutch fork in my case despite other posts citing that, but it’s like $30, and bought that at the stealer Either of those could have been contributing or casual factors. I don’t have the time to keep messing around with this damn SMG crap. Doing all of this step by step to figure out the actual cause is doable, but I’m not going to drop the trans 2 more times just to find out and mess with the driveshaft mounting also. That ends up being a solid 8 hrs of work. This is why at some point just throwing parts at it makes sense. If I simply add up all the time I’ve spent on this, excluding and research or videoing or anything else, it is way over 40 hrs, probably a solid 4 hrs of cumulative bleeding.

I was getting the same messages (refer to initial post) on complete trans adapt on all combos until I did the final swap (which is described in post 25)

I won’t declare total success till I drive it and get no SMG codes or cogs, so we’ll see.
 

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I was asking in what adaptation it failed, that may indicate something at that point. Was not not necessary to drop the box You did a good experiment by installing different harness on the block but it failed but that may not was the reason of failure, the step that failed may reveal more info about the cause. The system complexity lay mainly on the software and logic written into the ECU memory and we can't beat that. I think you will be fine so far, adaptation is very important factor that means your system is within the tolerances stored in the memory and that tolerances what make the ECU throw fault codes. From reading lots of thread, documents and owners troubles, failures appeared to be more consistent at some degree.
 

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Discussion Starter #31
Many times there are drivablity errors that happen with no codes displayed in the ISTA scan, but they exist in the history memory. I posted what I did to help others who may come along later and read it, otherwise it's just me rambling. Perhaps other than Jim Colley, I haven't encountered anyone who has done the trans adaptations on an unmounted trans, similarly the 4 different combinations possible with 2 actuators and 2 gear strip sensors. Non working combinations (for me) resulted in the errors stated in prior posts.

I was asking in what adaptation it failed, that may indicate something at that point.
There are 3 adaptations required. I only had issues with the complete trans and clutch-slip. I talked about this extensively already, there is also a video. refer to Post #1. Post #25 describes what was done to address the trans teach-in situation. These were done with the trans not mounted to the engine as I had described in Post#15 in the last paragraph, it worked perfectly and allowed me to inspect the values in my other SMG controller also.

Was not not necessary to drop the box You did a good experiment by installing different harness on the block but it failed but that may not was the reason of failure, the step that failed may reveal more info about the cause.
I don't understand what you are talking about. I have not found a way to replace the clutch fork without removing the trans. Removing the gear strip sensor is technically doable with the trans still mounted and it tilted back, but I'm not a midget, and when you open up the hydraulics it's essential to be clean when sealing things up. Removing and replacing the actuator block is not possible without dropping the trans. I mentioned in post 15, the plan and post 25 the result. I don't know what you are talking about regarding different harness on the block, except possibly the gear strip sensor.

adaptation is very important factor that means your system is within the tolerances stored in the memory and that tolerances what make the ECU throw fault codes.
No not really, they are not merely values within a tolerance, adaptations are really calibration values. 4F66 and 4F67 are codes that are set when a new adaption is attempted and completed unsuccessfully. Upon the successful adaption the new values are displayed and written to memory. ISTA shows what the prior values were, in my case when trans adapt was successful, it showed the prior values to be all zero, indicating an uninitialized state.
 

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When I said "You don't have to drop the transmission" i meant, you don't have to drop it for the the second time, in addition , just to troubleshoot why it failed when you installed the gear position harness that you repaired on the replacement block.
It could have failed of other reason other what is known "installing a position sensor on different block" for the sake of the experiment. I will include a quote from old thread by " jcolly" used the same method I am using to troublshoot and understand the eroor generated by the ECU it also he used the reading from Inpa position sensor status page, that values may not be valueable when the transmission is removed, but it does mean something when it is installed, because it may indicate a hydraulic problem,, the numbers is different when the transmission installed, but when the transmission removed you will see a prset values may be used for diagnosing or failsafe opeartion.
If both of those test out without problem, it is possible that there is a problem in the actuator block. You can monitor the sensors in INPA via the "read status" screen and look at the shift rod positions. If there is an error on the shift rod sensor strip, it may indicate erratic behavior here. This is not unusual as the insulation on these strips tends to decay and rot away.

The shop isn't in left field wanting to pull the actuator block off the top of the transmission to inspect the mating of the shift pistons to the shift rod carriers, but there are a few steps they can look at first without dropping the transmission.
 

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Discussion Starter #33
The only reason why I tried non matched sensors and blocks was 1) to see what the errors codes/adaptation failures would be. 2) I could do that effectively with out have to install/drop the trans since I have a spare trans to module harness and a trans jack that allows me to raise the trans high enough. I reported the findings for ppl to see when or if they ever encounter these errors or noises.

the original actuator block may be the culprit. I can’t exclude it, but it did seem to work and not make rattle noises before I dropped the trans to replace the original flywheel and clutch. It could have been my shoddy soldering and repinning of the strip sensor although there’s no real way to check that other than reinstalling it and looking at values. I did that almost a month ago though. I did have to drop the trans since it was not adapting the trans or the slip point. I also had to replace the fork, and I check the clutch installation again and everything else in the bellhousing. I used the bmw alignment and holding tool for the clutch install, but someone else reported they had a “bent“ clutch cover (it was new). Therefore I it was always the case i had to drop the trans as mentioned in #15.

I’m not following the remainder of what you posted here, I don’t see how it relates to my issues, but perhaps I’m just dense. I resolved all the adaptation issues successfully and did replace some parts that I don’t know for a fact were bad. It’s time and effort vs. money.
 
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