Defrost/de-fog/heater on driver's side view mirror broken

[jbroses]

The defrost/de-fog/heater on my driver's side view mirror of my '95 850 wagon is no longer working. The passenger side view mirror works fine. I was hit by an insane driver and had to have the driver's side view mirror replaced 2 years ago, but the heater worked fine last winter.

Is there a way to fix this? Is there an easy way to disconnect the mirror so I can look to see if it's something simple (loose cable) that I can fix just by opening it up? In a worst case scenario, how hard is it to replace the entire mirror?

Thanks for any help!