Dmitryl, something seems wrong with almost all of your readings.
The throttle supply voltage should be measured on
T1/5V, not
T2,
T2 should show the throttle signal voltage being returned to the controller via the throttle control.
The low reading of 4.8V on the
G pin is definitely not right, as this has to be linked to the B+ supply in order to energise the controller, so you should have obtained a voltage reading equivalent to the battery voltage on the
G pin.
Either your battery/
BMS is faulty, or you have a very poor connection somewhere on the wire between
B+ and the
G pin.
I suggest you check the voltage reading across
B+ and
B- connectors on the controller to make sure that the required battery voltage is actually reaching the controller.
Alan