I warmly welcome, I recently tried to connect my sharan to a computer using CDIFA and unfortunately I get a communication error. I started to check the cable - the K line and it turns out that everything is fine from the ODB socket to the meter and from the immobilizer plug to the ECU. Is there anything on the meter clocks that can block the connection?
You only have no communication with the engine controller? The K line for the engine controller goes through the immo box. If there is a problem there should be communication with the immo box. Short-circuit K and W to immo forest and diagnosis should return. They are probably gray-white or white-gray wires.
maybe something is happening with the cables because when I bought it, there were no 2 pieces in the fuse socket (there were empty spaces) and when I refilled them, the battery discharged after the night ...
Added after 2 [minutes]:
You only have no communication with the engine controller?
I have a total lack of communication. Only when connecting "for a short time", as I mentioned before, I connected to the engine controller, I could not cope with others.
Check the voltage on the K line. Under the cockpit, somewhere in the upper left corner there were connectors where all the K line wires come together. Unpin all in turn until you find what is blocking.
I finally found time to review the installation. It turned out that someone was already looking for something and the beam insulation was cut open. 4 yellow-black welded cables protruded from the cut insulation - visible in the photo. In addition, the gray cable with a white K line strip from the OBD socket is also welded to 4 others - also visible in the picture. These welds are factory or are they someone's makeover?
These heated wires from the first photo are connected K lines. I unraveled them all and it turned out that the connection was blocked by one of them - most likely from reheating (most likely because I have not checked yet and the computer can not connect now only with reheating).