There are two possible reasons for the GP-Probe TGE2 to indicate the error:


Reason 1:  Short circuit in the GNSS antenna or RF cable.


Solution 1: Replace the GNSS antenna or RF cable.


Reason 2:  A passive GNSS antenna is being used while the GP-Probe's GNSS antenna power supply is enabled.


Solution 2: Disable the antenna power supply for this channel in the configuration panel: