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Replacement parts for WHIRLPOOL GBS307PDQ9 | AppliancePartsPros.com

Sounds like the high limit thermostat (Item 37 in Section 1) has opened.
I would check the power to the unit first. Electronics and lights only require half the line (120 volts) whkile the elements require bothe sides (240 volts)
See bootom of this post,

Looks like this is sold as single or dual oven units.
Remove power from the unit.
Remove one wire from the thermostat and check it with a meter.
Should be 0 ohms.

This should help with your repair.
https://secured.whirlpool.com/Service/SrvTechAdm.nsf/2cd44500d572193285256a45004fd9d6/7d69e72584ddde3385256a7e00524e76/$FILE/8178007.pdf

Power Check
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.
[COLOR="Red"]Be careful as 240 volts is lethal !!! [/COLOR]