I have experienced the strangest problem with my truck. The power locks, side mirrors, and interior lights all stoped working. My locks will function normally when I use the remote entry. But no response at all from the door controlls. Power windows work fine from both doors. I checked all the fuses and couldn't find any blown. Is there a master relay somewhere? This is a 2000 silverado 2wd 4.8l v-8. Any sugestions would be apprecieated.