What type of radar is it? The Bendix line of indicators use a round
'cannon' type connector on the back pull the indicator and see if
it's connected. Very simple use a 3 /32 allen wrench to unlock the
pawl slide it out and see if it's connected.

Did that and checked up front in the radome as well- everything seemed to be
connected. My guess is a crimped or loose wire in the cannon plug. It is an
RDR 160.