The LG microwave model number LMV1630BB is a combination unit made for installation over the range in a kitchen. It provides both a standard microwave and an oven hood that may be turned on to extract steam, smoke and smells while cooking on the range. Like other microwaves, the LG LMV1630BB contains fuses, which may occasionally burn out and prevent the microwave from operating. Though LG recommends calling in an LG appliance specialist for changing the fuses on an LG microwave, you may be able to change the fuse yourself.
Get beneath the LG microwave, and grasp it on the bottom at either end. Lift the microwave up slightly, and pull it out from the wall to remove it from the mounting plate.
Turn the microwave onto its face on a soft rug or blanket. Remove the screws from the back panel of the microwave, and slide the panel upward to take it off the unit.
Look for the three fuses in the LG microwave -- one at the lower-right corner, one in the upper-right corner and one in the top center. Check each of the fuses to see if any of them look dark in color; this indicates a burned-out fuse.
Remove the burned-out fuse by gripping it firmly and pulling it away from the wall of the microwave. Once the fuse is removed, press the new fuse into the same position in the microwave until it clicks into place.
Slide the back panel onto the microwave, and replace the screws. Lift the microwave into the space beneath the cabinet from which it was removed, holding it slightly higher than the mounting plate, and lower the microwave until it catches on the mounting plate.