Hi klem, reading your last message I am not sure you are applying the right key sequence. The order matters. The radar won't turn on while in NAV mode, so you should:
- first switch to BVR mode by pressing '2'
- then activate the radar with 'I'. This will also display info in the hud
These keys are default ones in all fc3 planes so you would not need to remap them.
hope it helps.