Lost machine inspector xyz position

PREVIOUSLY HOMING homing and setting XYZ work zero always resulted in predictable xyz in machine inspector/
Now no XYZ other than 000 000 on both machine and work
When I jog no change in XYZ
When I issue G commands G90 goes to unknown coordinate and didnt stop – I think this was in x movement
G91 works fine I believe and jogging works fine
I have the gshield xcarve with arduino
will a loose z probe wire do it?