Omegas plus golf6

Good morning, I have a golf 6 bifuel
with landi system I have the PTFtdi8
interface cable, I wanted to connect to
the control unit to make the diagnosis,
because it no longer switches to gas.
The program I can use to access my
ECU Model ECU: LC02 Firmware
version: VW202043G24 is called
PlusMax 2010 . But I can't connect!!
After a few seconds under lock and the
key the LEDs turn off while with the
engine running the switch and the LEDs
are turned on try to make the gas
switch in fact you hear Ev2 of the tank
close but it does not switch and the
alarm goes.
Most likely the 12V on pin 5 under lock
and key fail after a few seconds under
lock and I don't know why maybe you
close the security relay ?? I tried to
power it on the bench to read the
errors, only with the 12 V on pin 15-43
-5 and the 22 53 pin masses and with
the interface cable on pin 38-39 - 10
-11 but I can't connect I don't know if it
depends on the cable on the software
or the ECU
. Who can help me ??
Thank you !!!