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Bissell,
Have you ever heard the pump running, or by chance ever monitored the pump pressure on ISTA/INPA?
I checked the wiring diagrams the other day and the plcd and pressure sensor share the same 5v output. Since pressure seems to read fine there's no point in checking that 5v output.
PLCD pin 7 and Pressure sensor pin 1 both have 5V and share with Gear position pin 3 5V from ECU pin 34, the issue is PLCD pin 6 and Pressure sensor pin 3 Ground is being shared with Gear position sensor pin 8 Ground. So if Gear position pin 3 5V is shorted with any ground or signal ground from Gear position sensor then it will have short in PLCD and Pressure sensor. this explain why the PLCD is not reading. For pressure sensor I doubt it is reading or ever the pump turned on because the pressure sensor indirectly control the pump operation. Unless the system designed for the pump to run without pressure sensor operation.
As for the gear position sensor (GPS?) supply it is shown using a different ecu pin but that doesn't mean they could be tied internally.
The diagram clearly shows the 2 5V main channels is pin 3 and 4, and pin 4 feeds pin 1 and 9 internally because there is no wiring for pin 1 and pin 9, to power and monitor all 4 pistons. So basically each piston position required a 5V sensor power input.
 

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Discussion Starter #162
I have had some different thoughts on how to isolate the wires including:
1) spray coating.
2) adhesive.
3) shrink wrap.
4) wire loom.

I think the best is to shrink wrap for longevity. Then cover in wire loom and tape also for longevity.

I will remove that orange tape first. It looks to me like it could be avionics C-4 tape. Then I want to remove one pin from the connector at a time and shrink wrap.

I will try to do it without removing transmission first. It id going to be tedious with the tight quarters. But hopefully worth it in the long run.

Those connectors have 'face plates' on them that will make it difficult to insert into in order to release the pins. Does anyone have experience with releasing the pins on these particular connectors?
 

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I can tell that you were able to start the engine, does it starts with SMG ECU all plugs connected?
Have you seen the pressure value other than 0?
what happen when you start the car and try to shift?
 

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Discussion Starter #165
Yes the engine runs. And all the SMG ECU plugs are connected.

I can shift through software (INPA) but not using the shifter. The one time I was able to unlock the shifter, I was still unable to shift with it.
I have only seen the pressure at 0. But I only looked at it once. I am not sure if I had accidently reduced the pressure through INPA or if I am getting a false reading. After all you need presurre to shift even if it is through software (INPA). At least that is what I believe to be the case.

Can anyone tell me how to disassemble the connector from the SMG for the gear selector and for the clutch position sensor?
 

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Sorry I'm a bit late to the game but you MUST fix the wiring before you go any further. You have INPA going and that is great but it will not fix the wiring. It is a known problem and apparently the PO already tried to fix it. You can try and contact Jim at FAMS and have him overhaul the entire valve body or try and DYI. Shrink wrap each wire and then the bundle, do it once do it right. You have come this far don't try and short cut the SMG. I would also replace all of the o-rings on the solenoids.
 

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I asked those question just to learn more about the logic in the ECU. I wouldn't have expected the car nor the pump run. My car didn't start because of low pressure due to almost empty reservoir when I bought it. The only way the car start if you disconnect M4 connector, M4 connector has all the control for the SMG. The M3 connector has all the data from the cabin for example shifter output data. When you posted the ISTA status pages the other day some signal of the status on selector lever page was blank. I wondered why.
You need hydraulic pressure force to either manually shift by software or normal operation, without it you will only shift electronically and have a display, but not actual gear shift at the transmission.
Based on you continuity finding, the pressure sensor is shorted, I believe you have false pressure reading ( 0 Psi) if you want to confirm, trigger the pump to ON position then OFF and exit the page and go back to the sensor status page to read the pressure.(ISTA).
Another thing to do, try to test the accumulator you will see the pressure drop during the test.
I don't think you can disassemble the gear position top head, just slide the heat shrink tube as far as you could.
 

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If the car started with the smg ecu connected then pressure is good.

The GPS wiring can be removed all the way to its PCB, there's a thread for it.
 

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The issue is how to uncover the circuit board and cover it again. It require special skills, knowledge and material. It is not straight forward job. Repair up to the head is sufficient in my opinion.
If you want to completely remove the sensor you will have to remove both proportional pressure solenoid valves to access the remaining screws holding it to the block.
 

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If you're familiar with a soldering iron you can do it. I did it. Used same potting compound as the op too. I've also stated that if I were to do it again I'd go the heat shrink route tho.
 

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Discussion Starter #171
The 2010 SMG have swapped into the 2006 car only has 52K miles. So I am not going to try to replace the solenoid o-rings on it. That may be a better DIY project for the 2006 transmission with 132K miles that is out of the car. I am all about learning as much about these cars as I can. After all they are sports cars. And the reality of sports cars is they are high maintenance. That leaves us two options:
1) learn them so you can do as much DIY as possible.
2) pay someone else a lot of money to do the same.

No one has responded to my question,
"Those connectors have 'face plates' on them that will make it difficult to insert into in order to release the pins. Does anyone have experience with releasing the pins on these particular connectors?"

So I will take a different approach. Does anyone know where I can purchase a replacement gear sensor connector between the SMG and SMG wire harness? This way I can see how it assembles. That will show my how to disassemble the one on my SMG. That last thing I want to do at this juncture is break the connector trying to get it apart.

Henry
 

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Discussion Starter #172
I attached three pictures of the connector. I just don't see a way to insert two needles/paper clips/etc through the small holes in the faceplate of the connector and push down the barbs in order to release the wire pins. Anyone?
 

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I think flaco posted some link, but I’m not sure if anybody bothered to really go into what is involved with depinning/repinning or excavating the potting compound and where to cut the case. I’ve done both and didn’t find much other than before and after pics, with a few shots in between. My resolding effort apparently was not successful but the wires and sensor were very spotty to begin with and I was already having gear selection issues when I got the car.

for heat shirk tubing, that’s also limited in helpfulness, because it will shrink in length too and what is then left exposed are the very areas that always are the first to show insulation degradation-the ends! I used the smallest dia shrink tube (3/16” as I recall) that was possible because unshrinked it has to fit over the rubber bushings, otherwise you can’t get the tube on. What also then happens on the sensor side is that the wires are all already “siamesed”, which will prevent any efforts to be able to get the shrink tubing to butt up against the sensor housing. between each wire you’re trying to wedge in 2x the thickness of the shrink tube side wall thickness. If you could wedge that in, you’re going to impart stress on the wires and the reality is that the total bundle size of all the wires will more than double. Therefore shrink tubing only protects the legnth of the wire not the ends. Mine on the good harness were fine so i put on shrink tube and silicone encased the end parts, so when it does degrade, it’s encapsulated by the silicone.

I don’t seem to recall anyone going into detail on how to repin these, I writing this from memory when I did this a few months back. It’s hard to describe.
Disassembling the hard shell is tricky but straightfoward, the outer black case goes over the inner white part, there are 4 fingers that hold it on,you need to release the tips of the 4 fingers then that releases the black part of the housing so you can slide it REARWARD away from the face, it is a “ring” that has the wires on the inside of it. So when it’s mated to the white inner part the black part is a ring where the inside of it is the white connector part.

with the black part out of the way, there are 2 pink clips that have fingers that allow it to be slide off left or right. Once those are gone, you have access to the terminal, which I think you press down on a retainer with a little pick and that allows you to unseat it (pull the back of the wire).
 

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Yes. On this one it helps to have 4 hands, to release those fingers on the back side, which you did not photograph. There are little fingers on the top, bottom, and each side.
 

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Discussion Starter #175
Thanks for the help on how to release the connector. I was able to do that.

I removed that orange adhesive (C4) tape. The wiring is worse than I thought. It appears to have been melted at some point. The wire coatings seem to have melted together. The wires may be touching there too.

Any hope I had of making this repair without removing the SMG from the car are now gone.

Once I remove the SMG, I will make the repairs to the wires and then reinstall the SMG. My game plan is:
1) remove the wrap of tape around the wire bundle.
2) shrink heat wrap each wire individually.
3) wrap the bundle in wire loom.
4) wrap wire loom with electric friction tape.
5) secure the ends of the electric tape wrap with small zip ties.

Any suggestions on to do this differently/better and make it a long lasting repair?

Henry
 
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