I took off full functional Chorus II and replaced it with Concert II device.

The swap was very straight forward, it took only few minutes and I got radio and cd player working.

But...

For some reason the Concert II does not switch on and off prior to car key position. It can only be powered on and off by pushing Volume button.

However backlights of the Concert are working ok -> so it does matter if car's lights are on or off and also the dispaly is dimming together with other instrument lights.

Also a bit wierd thing is that VCDS does not see the Concert II device at all ! So I'm not able to tune any parameters from 'Radio-56' module. Chorus II was responding ok to VCDS and 'Radio-56' was available.

Neither DIS is showing the name of the radio channel -> this was also working with old player.

So please,what could be the 'root cause' and any advices how to fix ?

Should I tune some other instrument parameter (by VCDS) to recognize Concert II corretly, or is there possibility that the CAN-interface is broken from the player (baklight/dimming is however working ok...)?