Remove it from the MSCAN and hopefully the MSCAN comes back on line.
Have you verified the power an
d ground wires are correct?
Can you verify that power is getting to the unit woth a volt meter?
Do we know if this TCU is even operational?
Ye power come to tcu, i test it with multimeter, i remove it, disconnect thr battery and ms work now. Idk if the unit work, i bought it as used
Sounds like the unit may be bad.
Or the hs test connector doesnt support it, maybye i should try connect it to dsp, there is more space at back
That is where my TCU is connected to the HS3 can and it works just fine.
So I see two options at this point.
Test your harness by plugging in a known good TCU into it. If it works your harness is good and you have a bad TCU. If it does not work then there is something wrong with your harness.
Or take your TCU and plug it into a car with a working TCU. If it works then it is your wiring harness. If it does not work, then your TCU is bad.
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Do you have some photos how you connect it? I still thinking what should be best. Thanks
No sorry I do not. My daughter currently is driving the car and I wont have access to it again for several months.
The TCU for the Mustangs that had one is mounted behind the left rear tail light. I had no space there, so I mounted it in a different area in the trunk. I ran the network cable to the front of the car. Used one pair of the twisted pair for the HS3 can using a Motocraft WPT-977 connector to plug into the test port next to the GWM as my access to thee HS3 can. In your pictures, it looks like the same connecter as I used on my car. For power, I ran two of the twisted pairs of tge network cable to the other side of the car where the BCM/fuse panel is located and connected one pair to a fuse tap and plugged it into the fuse location that Mustangs that had TCUs would use and the other pair I attached to a stud located nearby.
Before plugging in any connecors, I ran some checks to make sure there were no electrical shorts in my wiring and made sure power and ground were present and at the correct locations on the TCU connector. Double checked the HS3 can polarity. After all that I plugged in the HS3 can connector and then the TCU connector.
Then hooked Forscan up and started it without a saved profile. It was recognized by Forscan. Updated the calibration and strategy. Rebooted the module and then made asbuilt changes followed by starting the process to get it in the correct mode to accept Fordpass activation.
All that to say, if you are certain that your harness is good, then the TCU is not.
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Hello, so you take the hs3 from front test connector and go with that to back?
Yes. The single network cable takes HS3 and power from the front to the back of the car to where I mounted the TCU.
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Hello, so maybye i found why my tcu not working in my 2017 edge, i found somewhere that the JX7T-14G TCU using HS4. So i need downgrade the firmware TO JL3T-14G139 but this cant be done via forscan right?
No J series TCU uses HS4, Only the K series can use both HS3 or HS4 depending on calibration.
Hello, so what number i should look so i dont need downgrade firmware ?
Somewhere i see that the J series is HS3 and K HS4 and need downgrade.
Thanks
So i try other diagnostic, use the s max 2021 as the profile and i see the unit with some data, but can Edit them via this autel, so why forscan cant see the unit
This is something you should ask the Forscan group on their Forum. They will require you have a paid subscription though for tech help.
Hello i have paid version, but i figure it out, i delete profile and when it ask me if its my 17 or 18 i chose noe, the it want the pcm number and there is some how the number look so i Just write the number and the the forscan scan my car as some 2022 car and the tcu Come up. I downgrade the firmware and now see the number in sync, but the app still not get the data. Its bcs i dont have my 18,5 firmware in apim? But i have old hardware and see it cant be upgrade
Sounds like you figured it out than.
Ye but now what next 
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SO EDIT :it work now, but there is not remote start and unlock button, this in not working in EU or need make some Edit?
So now iam stuck that the fordpass after 2 min not connect to car, on sync there is not any accept
That may be it. I retrofitted a TCU in my 2015 Mustang and do not have remote start or lock/unlock on the Fordpass app while the car does have remote start from the keyfob.
I have a few more things to try on my end to see if it will be added but I would not hold my breath. It is likely something on the Ford side that prevents Fordpass from allowing it.
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