I cannot find info on the given model number.
Please check it.

Are you sure it has a 0 in it.
The below is for a JT912BF1BB
Parts for GE JT912BF1BB Oven - AppliancePartsPros.com

Check the power art the unit with a meter so you are sure you are getting 240 volts.
Check the voltage at the plug.
Your unit may be hard wired so you have to check it at the terminal strip.
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.
[COLOR="Red"]Be careful as 240 volts is lethal !!![/COLOR]

Next I would remove power from the unit and check the limit switch (item 159 in section 01)
Should be 0 ohms.

I am not sure what they are using the other switch for but if 159 is good then check 158.

Sometimes these just blow on there own especially if you ran a self clean cycle but it is best to check the below just in case something else caused it.

If the switch is open then it would be a good idea to also check the oven sensor should be about 1100 ohms at room temperature.

Also check that the fan works.

Once replaced check that the oven temperature is OK with a thermometer.
It may need calibrating.