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I don’t agree with your statement, it absolutely measures position, that’s what is done at various temperatures specifically for THAT actuator block, which is why sensors cannot be swapped.
The 1st pic in post 28 is supposed to be a read out from the gear position sensor, which is an array of 4 linear Hall effect sensors. I think the values can range from 0 to 1024. The computer infers “no gear selected” for each of the 4 rods by looking at the midpoint of the 2 extremes which are 2 different gears, so while there is no neutral sensor, it is inferred.

I believe what was said by others that it’s likely a fault in the wiring of the sensor which is leading to that 0 reading.
 

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I actually think he could command the trans to 6 or 7. It will be interesting for all of us. As I’ve stated in the other posts, partly as a result of what you videoed and what I saw myself on my gearbox.

If this gear command is indeed open loop, it just commands the solenoid to actuate X gear, and then assuming there is adequate pressure, it fires, without regard to the sensor feedback. This makes sense to me that the point of this command is to force a gear since there would be absolutely no other way to validate the box can go into gear. There are no levers. You have to be able to unit validate something as a diagnostic routine. The problem is that we don’t have the accompanying software document to explain the exact what and how behind the tests.
 

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Yes I edited my statement as it was confusing, and true there is no Neutral sensor, also it states that on the small windows on the Manual command Gear shift INPA page. Tough I expect he would have 2 zero for 6 and 7.
 

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Tough I expect he would have 2 zero for 6 and 7.
6 and 7 are the same rod. So no need to represent both. Not a bad design, but they effed all of us with that sh*tty wiring insulation. 0 in a “normal” sensor is likely not possible and may indicate an open circuit or shorted circuit. I think it ideally should be in the 500s so that would “indicate” center (neutral for that rod).
 

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Discussion Starter #47
I was catching up on the thread and it seems like this is him trying to get the car in gears via normal means not software commands, but open to interpretation. That’s why I say “command” when referring to software vs saying manually shift gear, which is really a “request” subject to the ECU’s programming, sensor feedback, and self preservation logic.
I was commanding the gear change.
 

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Discussion Starter #48
Yes Command is better to use to manually shift by the software. And i think he could unstuck it from 1st gear and commanded to another gear for example 6 and 7, because of the missing signal the ECU will not be able to shift it to 6 or 7. I still need to see Analogue Value 3 to confirm.
After I repair the gps I will test wiring to 6/7 solenoid and ohm resistance too. Then hopefully I will discover problem.
 

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Discussion Starter #51
Ok so after heat shrinking every wire and re-installing trans, here’s what I read from ista. Soo much smoother now.





 

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Discussion Starter #53
So I think I’m going to have to replace 5/3 solenoid. I got a limited gear selection cog yesterday after some m mode shenanigans. Happened after shifting to 6th. and full throttle. I’ll pull codes as soon as I can.
 

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Discussion Starter #55
why 3//5 in particular.
wait for the fault code.
I have one solenoid that has a lower impedance than the rest. I’m going to figure that was part of my previous problem, plus I didn’t put the solenoids back in the same position. I’m not stressed. I plan on pulling the motor to replace all the gaskets and do timing guides, 08 later vanos units and exhaust cam gear. So I’ll deal with it for now.
 

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Do you mean you swapped 6/7 solenoid with 3/5? If yes did the problem transferred.

all the solenoid I have ( total 13) ) tested was 3.2 ohm., I am not sure though if this is the magic number, I am happy as long as all of them tested the same, so I assumed they are ok. I recall you mentioned 2.9 when you were troubleshooting your 6/7 shift rod and I was under the assumption that all of them measured 2.9 not that they measured differently, so I didnt want to stand up and try to grab your attention that you might have a problem there.
 

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Discussion Starter #57
Yes when I sonic cleaned the solenoids I didn’t keep them in order except the clutch position solenoid. Even though it’s exactly the same as forward solenoids. One of the forward 4 solenoids was 2.5 instead of the 2.9 as the other 6 of them. Before I worked on the trans 1-2 shift was clunky and now it seems to have moved to 3-4. It only throws a cog when in m mode s6. And returns to normal after a few minute. When I get a chance I’ll run ista and see what code it is.
 

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Discussion Starter #58
Figured out my latest problem, I have a much better understanding of the smg electrical system now. The pump would loose conductivity when hot. No pump, no shifty. Strange problem hard to diagnose. I will have to get some pictures of ground location for pump makes it easy to test resistance of pump motor. Shout out to Robert at MLREng, super nice guy.
 
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