Burned out bulb

Found this post on another fixya-type site: below is the link..
Here's a repeat of Kai's instructions so you don't have to scroll down. I just replaced mine and it was a snap. Just a few Phillips screws and a few tugs. No need to pull the unit completely out as you can access the bulb after it's about half way. No need to disconnect any wiring harness except pulling the bulb out of its socket. I used the 10w (G4 12V) replacement bulb from Home Depot at $6. The light is a bit brighter but there've been no problems with fuses.

1) Turn off power to the unit
2) Open the lower oven door
3) Remove the side trim screws and pull the trims down and out.
4) Remove 2 screws on the sides of the control panel.
5) Open the Microwave door. Remove the 3 screws on the Air Vent Plastic Cover on top of the microwave. You can then remove the Air Vent Cover by pushing the control panel up and pull out slightly at the bottom.
6) Remove the 4 screws on the Air Vent Plastic Cover on top of the lower oven and remove the Air Vent Cover. (You may have to remove the left under side bracket of the Microwave door temporarily just for the Air Vent Cover to clear the screw of the bracket. Re-secure the side bracket of the Microwave door panel as the front panel may fall)
7) Remove the 2 screws which held the Microwave unit in place behind the Air Vent Cover on step 6.
8) Wiggle the Microwave unit out about half way to expose the light bulb unit on top center
9) Wiring to the Control Panel will prevent you from pulling the Microwave unit out any further. And you don't want to do that as the unit may fall. Space is cramped, but working carefully with pliers you should be able to release the springs which held down the light bulb unit and change the bulb.
http://www.fixed4free.com/answers.php?id=51232

Hi Not knowing the type of oven , I can only think it must be a screw type, try turning it to the left of course don't turn it too hard in case it comes out some other way , when yo replace the bulb wipe it off with a clean towel to remove your finger marks on the bulb it will last twice as long by doing this

My experience is that there is always at least one (and usually two) Phillips-head screws that secure a glass cover over the light bulb.

Unfortunately, a combination of heat and gunk can make these screws difficult to remove. Get a screwdriver with the proper-sized tip and a LARGE handle that will give you adequate torque, and try removing these screws. If they won't budge, try tapping the handle of the screwdriver LIGHTLY with a hammer... this might knock the gunk loose enough to turn the screws.

If that doesn't work, try using a ratchet with a Phillips-head fitting.

The most important thing is ensuring that your Phillips fits the screw(s). If not, you'll risk damaging the screw head(s) & then you'll have huge problems getting them out.

Once you get the screws out, remove the glass plate (you might need to lever it out with a flathead screwdriver). Clean it well. Unscrew & replace the light bulb. Reverse the steps for re-assembly. If the screws are gunky, or if the heads show any signs of damage, get some replacements at a hardware store (so you don't have trouble a few years from now!).

NORMALLY THERE ARE SCREWS TO REMOVE TO ACCESS A PANEL TO REMOVE THE LIGHT BULB. IF THERE ARE NOT, THEN THE EXTERIOR COVER MAY NEED TO BE REMOVED TO ACCESS THE LIGHT BULB. THIS EXTERIOR COVER HAS SCREWS.
MAKE SURE YOUR CIRCUIT BREAKER IS OFF BEFORE YOU TRY TO REPLACE THE BULB.

The glass cover over the bulb should screw off, remove the bulb and replace it with a new one of the correct type. Clean and replace the glass cover. Be careful not to use force which could break the glass and cause an injury. Make sure that the stove main switch is off. (The lamp cover may have a screw type or have a bayonet fitting).

Turn off at the wall and remove the light cover inside the oven by turning anticlockwise, this may be stiff, I use a well wrung out dishcloth.
You can see the bulb, which should be screwed out of its holder with care, also care when replacing. a I screwed mine in too hard and snapped the holder, but my oven is 5 years old.
Hope that helps

This worked like a charm ... actually it's easier than you might think. Just a few screws and a few tugs. Give it a shot.. I found a 10W (G4 style ... you'll see the difference when you get to the store) replacement bulb at Home Depot for $6:

1) Turn off power to the unit
2) Open the lower oven door
3) Remove the side trim screws and pull the trims down and out.
4) Remove 2 screws on the sides of the control panel.
5) Open the Microwave door. Remove the 3 screws on the Air Vent Plastic Cover on top of the microwave. You can then remove the Air Vent Cover by pushing the control panel up and pull out slightly at the bottom.
6) Remove the 4 screws on the Air Vent Plastic Cover on top of the lower oven and remove the Air Vent Cover. (You may have to remove the left under side bracket of the Microwave door temporarily just for the Air Vent Cover to clear the screw of the bracket. Re-secure the side bracket of the Microwave door panel as the front panel may fall)
7) Remove the 2 screws which held the Microwave unit in place behind the Air Vent Cover on step 6.
8) Wiggle the Microwave unit out about half way to expose the light bulb unit on top center
9) Wiring to the Control Panel will prevent you from pulling the Microwave unit out any further. And you don't want to do that as the unit may fall. Space is cramped, but working carefully with your fingers or pliers you should be able to release the springs which held down the light bulb unit and change the bulb.

for model 9815xub, the oven light consists of a light bulb cover(clear plastic, sometimes called lens) the light bulb receptacle( pressure mounted against the back wall of the oven ) and the light bulb, standard appliance bulb that screws into the receptacle, the same as the lens, it also screws into the receptacle, twist counter clockwise to remove both the lens and the bulb. as a reference try the following site:
www.partselect.com/ and type your model number in the window, then click on the oven cavity breakdown to view thwe assembly.

I can tell you it screws out . i had to break mine to get it out ( the bulb cover that is) Still had some thread left to wind back up.

Here is a simpler method from the same website mentioned in solution #1:
1) Turn off power to the unit
2) Open the lower oven door
3) Remove the side trim screws and pull the trims down and out.
4) Remove 2 screws on the sides of the control panel.
5) Open the Microwave door. Remove the 3 screws on the Air Vent Plastic Cover on top of the microwave. You can then remove the Air Vent Cover by pushing the control panel up and pull out slightly at the bottom.
6) Remove the 4 screws on the Air Vent Plastic Cover on top of the lower oven and remove the Air Vent Cover. (You may have to remove the left under side bracket of the Microwave door temporarily just for the Air Vent Cover to clear the screw of the bracket. Re-secure the side bracket of the Microwave door panel as the front panel may fall)
7) Remove the 2 screws which held the Microwave unit in place behind the Air Vent Cover on step 6.
8) Wiggle the Microwave unit out about half way to expose the light bulb unit on top center
9) Wiring to the Control Panel will prevent you from pulling the Microwave unit out any further. And you don't want to do that as the unit may fall. Space is cramped, but working carefully with pliers you should be able to release the springs which held down the light bulb unit and change the bulb.

By the way, the bulb is Osram 64405S. It's available online for about $2.00 plus shipping.
See more info. at: http://www.howtomendit.com/answers.php?id=51232