Hy !

First off all, i am from France (south) , so y will try to write the best y can

My old 525tds E39 from touring 04/98 ...head gasket , 700000km... dead , it have the DSP S677a option with sat nav and 3:4 screen

y taked it all out , the wiring harness to and mounted it in my 525d touring 2001

So , radio works but the sounds go off after 5min , volume on the 3:4 works , but no screen ?

what y do not understand is that the 3:4 screen as only 2 connectors , one blue, one white , so how work the buttons on the steering wheel ? when nothing is connected to it ?

the sat nav y did not mounted it , its no in function anymore in europe , module tv either, did not mounted it , so there is something that y missing ? other wires connected to zke or lcm or other module ?

thanks !