These are only 12 volt bulbs and 5 watts, they blow out easily....If this does not fix it then the control is bad and is very expensive to replace, however I do believe it is the light as it is the same type I use in my microwave and it doesn't even last one year in there...Here are the instructions for bulb replacement for your unit...
Replacing the oven light:
1. Disconnect appliance at the main
power supply. Make sure the oven is cool
before replacing the light bulb.
2. Remove glass light cover by grasping the
front edge of the cover and pulling it away
from the side wall of the oven.
3. Remove the light bulb from its socket.
Replace the bulb with another halogen
bulb (12 volt, 5 watt maximum, available
at most hardware stores).
4. Replace the light cover by snapping it
back into wall. The light cover must be in
place when using the oven. The cover
protects the bulb from breaking and from
high oven temperatures.
5. Reconnect appliance at the main power
NOTE: On both single and double ovens,
the oven lights will not work during the Self-