Hi Leigh Sir! Would you be able to share your thoughts on what could be causing this error? How would resolve this issue? U0402 – Invalid data received – transmission control module (TCM) Probable Cause: Wiring, Defective TCM, Defective transmission, PCM
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Hi Ken,
Have you ever felt the abnormal from transmission? If not, I suggest deleting the error code and read again after a few months. If the error code continued, you have to check everything from wiring, TCM, to transmission.
thanks for the quick reply! the only thing i feel is maybe a slight un-smoothness from downshifting - a little bit of a bump I would guess between 4 to 3 or 3 to 2. I was not able to delete this code with a OBD2 reader ( https://www.amazon.ca/Panlong-Scanner-Diagnostic-Reader-Engine/dp/B07RKVR4QN) My research is suggesting that transmission error codes cant be deleted with this simple ODB2 readers. Is this true? My thinking of unplugging the battery for a few days for the car to reset -- will this work?
That reader can not delete the error code. Disconnecting the battery won't delete the error code.
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@Senior Leigh | 老李 thank you!
Also, is the TCM located at the front passenger under the glove compartment? I pulled it back and saw a metal bracket which I think is where the TCM is mounted on. Are you able to share some diagrams and documents to help me diagnosis this? Much appreciated!
The TCM is in the transmission case, soaked in the ATF.
You might to take a look at the video https://youtu.be/SaAqai5T8FA
Here is the document of removing the TCM from the transmission was pulled from MB WIS ⬇️
TY 李 Sir! you are very kind.