airsensor monoshock

[mopipi20]

I bought a secondhand monoshock,at a tankstation i putted new air in the shock ,5bar would do i thougt,but wen i tested the airsensor with a ohm meter it pointed zero resistens ,strange it was,

do i have a worn out sensor,or do i have to put more air in it

at home i putted the monoshock in water but there are no leaks.