Is the door unlocked?
When you program it to bake does it go in to self clean?
It will likely be the sensor.
Remove it and have a parts store measure the ohm's with a new one. It is likely reading over 600 deg and will give the clean light. The other thing to check is the swich on the lock assembly. Make sure the swich on it clicks when you push the actuator. Sometimes starting another clean cycle and canceling it after a few minutes will reset the lock.
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Have you removed the back panel? You may be able to get to the lock from here. Unscrew it and remove from the back. If not the screws under the burner caps have to be removed and there are two spring clips that are located about 1 1/2" in from each side to pop the top.