2003 Chevy Astro ELECTRIC DOOR LOCKS

Electrical problem
2003 Chevy Astro Two Wheel Drive Automatic

QUESTION ???

AT THE REAR OF THE VAN I HAVE THREE DOORS, TWO HALF DOORS AND A UPPER GLASS DOOR THE DOOR LOCK DOES NOT UNLOCK WITH THE REMOTE BUTTON OR THE KEY... ALL THE OTHER DOORS UNLOCK AND LOCK WITH THE REMOTE BUTTON ONLY, THE INSIDE BUTONS DO NOT WORK.. WHAT FUSE DOES IT WORK OFF OF AND WHAT ELSE SHOULD I LOOK FOR???