I have a new Sony PCV-W1 (piece of sh**) and unless I run in safe mode the instrument panel is blank. The mouse pointer still shows instrument descriptions but just a black hole where the instruments should be. The radio stack and GPS display come up OK? have tried
Updating card driver (SIS 651)
Changing settings within FS2004
Changing settings as regards display properties etc.
Checked memeory for video card 32mb
In fact I have gone right though the MS list and still no result.
Anybody had this problem?
Here is one similar to your's.
https://forum.flyawaysimulation.com/forum/topic/1114/no-instrument-in-cockpit-view/
In your case it may be either drivers for the video and sound cards or time for a reinstall of your OS.