4L80E error code 73 - trans light always on

[RF5]

Then it is definitely coming from the TCM, as I said as long as you have a 73 code that light should be on, since you are doing board level repair I would lok at any electrolytic or tantalum capacitors on the board, I would try to follow the circuit board traces going to the pins associated with the PCS and just shotgun any caps along the way.

Yes, you’re right, thanks again for the help.
I would need a circuit board diagram to check the components related to PCS. Do you know if there is available the diagram?

 

[Mogman]

Yes, you’re right, thanks again for the help.
I would need a circuit board diagram to check the components related to PCS. Do you know if there is available the diagram?

Not that I know of, why I said to follow the traces.

 

[RF5]

I did not see, you have the correct reading (ohms) at the associated pins (C15-D16) around 3-5 ohms at the PCS, yes?

Yes, I did.