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Replacement parts for RS675PXYH models | AppliancePartsPros.com

Here is the tech sheet
http://www.servicematters.com/d...0Sheet%20-%203182752.pdf

This problem is a bit of a puzzler because the bake element does come on initially. On many units during bake, the broil and bake elements cycle but this does not seem to be working.
My guess would be that the control board is toast.

I would check the temperature sensor though this would be a long shot.
If the sensor is registering a low temperature due to a fault the unit should still cycle the elements.

I would check all connections/wires (disconnect and reconnect them) from the control to the bake element. Perhaps a connection is expanding and opening when the unit starts to heat up and this is why the bake element runs when the unit is cold.
Note that this may be occuring in the bake element itself.
Only way to tell is monitor the voltage going to the element if it is receiving voltage but not heating it is toast.
Be very careful if you attempt this as 240 volts is lethal!!!

Here is a good site with troubleshooting help.
http://www.applianceaid.com/elecrange.html

If it is the control board, it may make more sense to replace the unit.