Thanx for everybody, I got it.
First bit is precat O2, second is postcat. So for 1.8t I should change it from 3 to 1 if I dont need postcat probe.
Here is clear description, might be useful for others, found in FR of ME7.3, section APP GGLSH 3.30 Application hint
CWKONLS :
----------->
Code word in % PROKON :
Sensors present upstream of the catalyst --->
Bank1: B lsv by Bit 0 = 1
Bank2: B lsv2 by Bit 4 = 16
(gives 17 as the sum)
Sensors present downstream of the catalyst -->
Bank1: B lsh by bit 1 = 2
Bank2: B lsh2 by bit 5 = 32
(gives 34 as the sum)
For all 4 installed seensors: CWKONLS = 51