VTOL GPS issue

Hello everybody,
I have a pixhawk 1 which was installed on a quad crashed into water. I made the drying maintenance and I was able to upload the px4 1.10 into it. The mag , barometer, gyro and accelerometer all works perfectly except that I couldn’t power it from the power port, the ACT led doesn’t blink and the gps couldn’t be read from any of the serial ports. My plan is to use it on a VTOL quadplane and only for the Vtakeoff and Vlanding and make the transistion. My little question is if there is a solution for the interfaces problem, But the big question is if I can use it as is without gps on VTOL without problems?( I don’t want any of the gps based modes.)
Best regards for all.