The TCAS on the QW146 is not displaying any traffic. To solve this, please follow these steps:
Navigate to the SimObjects\Airplanes\QualityWings Avro Common folder.
You will find several folders whose names begin with "panel.".
Inside each of these folders, there is a panel.cfg file. Back up each of these files before proceeding.
Open each panel.cfg file and locate the following line:
gaugexx=QwBAe146_TCAS!TCAS, 0,0,1,1
Change this line to:
gaugexx=QwBAe146_TCAS!Logic, 0,0,1,1
Save the file after making the change.
Once you have done this for all the relevant panel.cfg files, the problem should be resolved, and you can enjoy flying this graceful bird.