Sounds like some other textures are missing.
Go to flightsim.com and search for 'gauge recover', download the program, run, and uncheck everything but restore (restaure) the effects folder and change to 'Replaces only the missing files'.
(I uncheck the other stuff because I have replaced my gps gauges with those from OZX which show AI aircraft [fun to find and buzz them with a fast mover], and some effects removing clumps, etc.)
You should probably copy the folder before you run the program so you can compare after, I have renamed some of my effects to disable (like fx_skidmark.fx and fx_snowenginewash.fx for FPS and display anomoly reasons), if they are reinstated you will want to delete for the reasons you disabled in the first place.
Hope this helps.