Transmission issue help

[asherkimball]

Was driving up a hill yesterday and my car jerked but kept moving forward and my PRNDS started blinking. The car drove ok and I got it home but the flashing continued and the check engine light turned on.
The code was P0717 (no signal from input/shaft sensor A) and the TCM codes were 19143 (unexpected gear disengagement) and 17115 (sporadic incorrect gear ratio).

The transmission was a little jerky up until now and the rpm’s would surge before going into neutral sometime.

What do you all think the cause is? It is just a failing trans speed sensor? Let me know before I throw parts at this barstewards

[asherkimball]

Replaced the speed/temp sensor, was pretty hard job but went well. Unfortunately this did not fix the issu, still intermittent loss of signal from sensor causing limp mode. I’m thinking possible wiring issue(really should’ve checked this first) or possible tcm/circuit board issue. Anyone let me know what you guys think pls!

[Marticus]

Sorry im not going to offer much advice except to say thatbi feel your pain, ive been dealing with intermittent tcm communication issues for months now and havent been able to pinnit down, im hoping you have better luck than i have!

[asherkimball]

Sorry im not going to offer much advice except to say thatbi feel your pain, ive been dealing with intermittent tcm communication issues for months now and havent been able to pinnit down, im hoping you have better luck than i have!

I fixed it!! It was a helluva journey but she done. Turns out there was a small broken wire INSIDE the TCM. I went through all the wiring diagrams to determine it was in there. Fixing it was pretty sketchy but I pulled the mechatronic again and dremeled the white rectangular cover off and found my tiny broken wire(which still made Contact but I’m guess separated during occasionally from vibrations explaining the intermittent disconnect). Turns out the wires are aluminum so soldering it back was difficult but I turned the soldering iron to max heat and used this special flux I got on Amazon as well as silver solder(tin seemed to work too but slight less cleanly)and it soldered fine. After checking for continuity in the speed sensors connector on the outside of the tcu back to the transmissions connector(circlular one), I then used RTV silicone to seal the cover back on. Put everything back to together, added trans fluid, cleared the tcm codes and it’s had no issues since! (SHOUT OUT JAX’S VIDEO ON YOUTUBE FOR SHOWING ME THIS METHOD)

[mjmallia]

Well done!