See the attachment for the tech sheet.

Since you mentioned the interior light I am assuming that it worked before this problem.

The same 120 volt power runs the light as runs the motor (L1 to Neutral).
So I would start by checking the power to the unit.

Try flipping the breaker off/on slowly a couple times.
Sometimes you can loose half the line without actually tripping the breaker.
If this does nothing, check the voltage at the plug
L1 to L2 should be 240 volts
L1 to Neutral and L2 to Neutral, both should be 120 volts.
If OK
Unplug the unit and check the wires at the terminal strip in the machine to make sure none are loose or burned out
If OK
Check the power at the terminal strip.
Do this with the heater off and on.
[COLOR="Red"]Be careful as 240 volts is lethal !!![/COLOR]

Next would be the door switch.
It turns the light on when the door is open but also provides power to the motor when the door is closed.