A52 CarKit activation

I'm trying activate the CarKit in my A52 with a microcontroller (89C51). I have an original CarKit from Siemens and it send the following command to the phone to activate the CarKit mode:

RX = cellphone recieve
TX = cellphone Transmit

RX - AT^SACD=2,"1A" [0D 0A]
TX - AT^SACD=2,"1A" [0D 0A]
TX - OK [0D 0A]

RX - AT^SACD=2,"1A,00,2,1" [0D 0A]
TX - AT^SACD=2,"1A,00,2,1" [0D 0A]
TX - OK [0D 0A]

TX - ^SACD: 1A,01,1,0,SSSSSSSSSSSSSSSS [0D 0A](16 numbers Hexa)

RX - AT^SACD=2,"1A,01,2,RRRRRRRRRRRRRRRR" [0D 0A] (16 numbers Hexa)
TX - OK [0D 0A]

The cellphone sent the S's numbers to carkit and it answer the R's numbres.

How can I calculate the R's numbers ? It's seens a kind of CRC of the given S's numbers.

Thanks for the help !

PS: Example of R and S numbers:

^SACD: 1A,01,1,0,F7342B2832344221
AT^SACD=2,"1A,01,2,442AB576CC3CEBA0"

Here some other numbers and anwers that I got:

^SACD: 1A,01,1,0,C6457F2832344221 _________> Line 1 (from cell)
AT^SACD=2,"1A,01,2,AA1297437FDA0270"______> Line 2 (from CarKit)

^SACD: 1A,01,1,0,256C152832344221
AT^SACD=2,"1A,01,2,BA130F662C293FAF"

^SACD: 1A,01,1,0,F7342B2832344221
AT^SACD=2,"1A,01,2,442AB576CC3CEBA0"

^SACD: 1A,01,1,0,C768432832344221
AT^SACD=2,"1A,01,2,846384608FC4073D"

^SACD: 1A,01,1,0,C6457F2832344221
AT^SACD=2,"1A,01,2,AA1297437FDA0270"

^SACD: 1A,01,1,0,256C152832344221
AT^SACD=2,"1A,01,2,BA130F662C293FAF"

^SACD: 1A,01,1,0,F7342B2832344221
AT^SACD=2,"1A,01,2,442AB576CC3CEBA0"

^SACD: 1A,01,1,0,C768432832344221
AT^SACD=2,"1A,01,2,846384608FC4073D"

^SACD: 1A,01,1,0,CB9A432832344221
AT^SACD=2,"1A,01,2,BFFDA9D02618D583"

^SACD: 1A,01,1,0,3A022F2B32344221
AT^SACD=2,"1A,01,2,42924398E6516A9D"

^SACD: 1A,01,1,0,EDC82F2B32344221
AT^SACD=2,"1A,01,2,4FBFC041425DB2BB"

^SACD: 1A,01,1,0,306CAD2832344221
AT^SACD=2,"1A,01,2,85B48D4E04498E3D"

^SACD: 1A,01,1,0,FC1A2B2832344221
AT^SACD=2,"1A,01,2,2361E4AD899EA2A0"

^SACD: 1A,01,1,0,D7E22F2B32344221
AT^SACD=2,"1A,01,2,6D82EFE63F77854D"

^SACD: 1A,01,1,0,CB9A432832344221
AT^SACD=2,"1A,01,2,BFFDA9D02618D583"

^SACD: 1A,01,1,0,3A022F2B32344221
AT^SACD=2,"1A,01,2,42924398E6516A9D"

^SACD: 1A,01,1,0,EDC82F2B32344221
AT^SACD=2,"1A,01,2,4FBFC041425DB2BB"

^SACD: 1A,01,1,0,306CAD2832344221
AT^SACD=2,"1A,01,2,85B48D4E04498E3D"

Any Idea how can I calculate , from 8 bytes numbers of the Line 1, the 8 byte numbers of the line 2?

TIA

MOV