D3 Automatic no coms

Finally bottomed the prob
No comms reported various module and to ECU
Pulled out wiring harness - there are two components. One goes to the auto trans plug and the other goes to the rear transmission case plugs. There is wide misconception - the TCU is inside the auto transmission by removing the sump pan. The Integrated transmission ecu is next to the main ecu and controls the transmission after the auto transmission.

I checked earths and supply volts in the harness, re did the canbus splice in the wiring. At the ends of the harness to the auto plug and the difficult connector under the ECU I checked out good supply and earth. Checking the canbus wires local to these there were problems.

There was no canbus out put from the TCU even tho there was supply and earth at the plug.
So pointing to TCU problem. Avoiding huge costs decided to attempt break into TCU whatever cost - nothing to lose. You can undo it I used clothes pegs a gap supports carefully opening it up- there are hidden clasps to release
Once opened up all is revealed - water corrosion of supply - see pics

Repaired and joy - fixed saved a lot

Useful information and pictures, may I ask what was the fix? Cleaning board/pins etc or replacement I presume