98 Regal : side-view power mirrors not working

My Regal 98 side-view power mirrors are not working, and I cannot find any info on what to do with them... How can one proceed to find out what is wrong with them ? I checked the only fuse (I found for them and it looks fine (not melted, fuse 6 in the fuse block on the passenger side of the instrument panel)... I also have Haynes' repair manual but there is nothing about power mirrors ...

The next step would be to see if the 12 volts from the fuse is getting to the switches which would require removing the switch assembly and checking voltage with a multimeter (DMM).

Thanks for the hint, BNaylor!
Could you briefly describe how to remove the switch assembly? I know how to use DMM's but don't know how to get into the switch assembly without damaging it or the door panel...
I have 98'Regal LS v6 3800 withOut supercharger.
Thanks again!