Comment on U0402 – Invalid data received – transmission control module (TCM) by Farrukh Sair

nickb2

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#2
I can't honestly answer this question. Ford quit making rangers in my part of the world in 2011. Ford has reinstalled the segment, even talking of bronco's also. But it is a 2.3l.

Sorry, canada doesn't have these trucks. The only 3.2l I have seen of this era is was in a transit. Should look like this.

Screenshot (320).png
 

nickb2

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#3
Normally, you will find most PCM/TCM's close to the PDC center. Ford has been doing this for years on the heels of spending less money on wiring, but mostly due to having multiplex communication. Having all modules close by reduces communication loss.

Try erasing the code and see if it comes back as active. If it comes back active, a CAN/BUS line may have been hijacked. Often times, aftermarket stuff installed incorrectly can cause a false flag code.

Just your question makes me wonder. Why do you automatically suspect the tcm? So step one of every trouble shoot chart you will come across when a "U" code is produced, is to erase it and see if it comes back as active. 90% of the time, it is a voltage loss or below B+ limits for some X reason.

Another thing to consider,
 

nickb2

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#5
Usually, anything with a 402 in it is invalid data or "high network traffic". So the TCM usually is ok at this time and should not be suspect as it IS reading the invalid data. Goal here is to pin point the source of the "high traffic" or what I call hijacked. Often, the abs module or it's network is at fault, not the TCM.

This is a generic code. Try to find a scanner that will read manufactuer codes. Those will help to pinpoint which module is out of sync or not sending back a network response.