How to be sure that Valve Body of transmission also needs to be replaced with Conductor plate in W 204 722.9XX mercedes benz



I have 2011 w 204 (C class mercedes 200 CGI Petrol).  Last week Check engine light came on. It is not flashing , but continues on even when I drive.  Went to MB dealer (I live in Delhi, India).  They run their diagnostic and it throws

ERROR 0606 : Component Y3/8n4- Fully integrated Transmission control unit is Faulty

Error : 0705 : Selection range sensor A has electrical fault

The service guy at the dealer says that both Valve body and Conductor plate needs to be changed . My control unit variant is VGS3_0403. I have read that in VGS 3 , conductor plate and valve body are separate.

Hence I do not understand why valve body also needs to be changed and why not problem can be solved by changing only the conductor plate?  is the service guy taking me for a ride ?


Thanks for help