Another not working diagun 2 (kline problem)

[kalosbg]

Hello,
i
have 2 diagun II, but one smart box cant work with k-line (only CAN).
I tried all solutions i found.
I know that problem is in logic board (not relay board).
I tried to change components form working board (from another diagun), i tried with U16, U17, Z3,Z4.
Please help me with advice.
Thanks!

[kalosbg]

Sergey guide me to find my fault.
My LPC2368 is damaged, can somebody help me to find may be open serial :)