Wes1450dn1bb stopped working. opened it up and found a burned and severed wire. is it advisable to repair the wire and place the oven back into service?

Check if the oven timer is on auto mode. If it is, turn it on to manual mode .
Remove the power cable from the outlet and wait for 20 minutes. As you plug your oven back in, the oven timer should reset as well .
Hold the timer buttons down at the same time to reset the timer .
Meter the thermostat out and see if it's open circuit .
Take the top off and inspect the selector switch and see if there are any signs of burning on the switch .
How to Repair ' Smeg duel fuel range cooker A1-7 Oven not working. (how-to-repair.com)

If you smelled a plastic burning smell you've burned some wiring somewhere. You would need to pull out the whole thing and start by looking at the back. I once had a dead mouse that had shorted across the relatively high voltage terminals common on most stoves. You should unplug the stove before doing anything like removing panels. Be very careful. Once you've found the problem you might need to call an electrician to fix it, depending on how brave you feel and where the problem is.

I'd be on the hunt for a burned fuse I could replace, on those two circuit panels. If no fuse(s) can be found, I would be sad to think the circuit board itself got fried, and new ones can be goofy expensive, so here's to you finding a burned fuse!!

That oven is very poorly rated and is prone to a lot of repairs. Most people advise to get something else. There is no common solution. I am sorry.

An oven thermostat is a switch that opens and closes in response to the temperature it senses. It is typically found in the control panel, where a liquid-filled temperature-sensing bulb senses and maintains the internal oven temperature by cycling heat on and off.
Before repairs or testing can begin you must disconnect the electricity at the fuse panel, at the circuit breaker panel, or by pulling the plug. Make sure the power is off before proceeding. A jolt from 220 volts can be fatal, use caution!

1. Access the oven thermostat, which is located in different places depending on the make and model: On freestanding ranges, access the thermostat by removing the screws that hold the back panel in place at both ends.On models with front-loading controls, remove the panel and tilt it for access. Be careful not to let the wires disconnect from their components. Some built-in models have a removable back splash. Lift the backsplash, rest it on the cook top and remove the screws from the back splash, which holds the rear panel. On wall ovens or eye-level ranges, access the control panel by opening the door and removing the screws that secure it. The screws may be under the exhaust hood or below the control panel. If the control panel is hinged, simply tilt it towards you. On some models both the rear and front control panels must be removed. The screws may be found on the trim and occasionally the trim must be removed.
2. When testing the thermostat switch contacts for continuity, refer to the wiring diagram and remove only those wires being tested - and only one pair at a time. Test switch contact terminals as per your wiring diagram. If the switch lacks continuity at any of the contact terminal points then the entire thermostat switch needs to be replaced.
3. Adjusting the thermostat: Test the oven temperature by placing the tester in the oven's center and leaving it for 30 minutes at 350 degrees. Record the minimum and maximum temperatures of three cycles, then add those figures together, divide the result by six and you have the oven's average temperature. If the average temperature is more than 25 degrees off, try calibrating the thermostat by following your appliance manual instructions for thermostat calibration. Normally, thermostats are calibrated by pulling the oven's thermostat knob off, turning the knob over and adjusting the calibration ring on the back. If your oven doesn't have a calibration ring you may need to replace the thermostat.
4. To remove the thermostat: Disconnect the capillary tube and push it through the back oven wall, being careful not to break the flammable capillary tube wire.
5. Remove the screws that secure the thermostat to the control panel and gently pull the thermostat out, leaving the wires in place.
6. To install a new thermostat, reverse the disassembly procedure, transferring the wires individually from the old unit to the new.

Hope this was helpful.Thanks for using fixya.

check that the fibre glass is still in place and has not been soacked with water, you can get some fibre glass from your local stores and wrape it just after openning the couvers and puting them back to place

You have a very good chance that it could simply be a faulty oven elemenr or burned wire or even an over temp. cutout switch. Have it checked by the technician and possibly get a quote..(When repair is done, you want to see faulty items).

breakers off ,,,back wall bottom center is a mounting plate 2 screws to take out the pull out wires and remove wires(careful not to let them slide back in)install new element...wires first the push back in place(no need to open back) don't forget breakers on now...you did it.... good for you.

Disconnect the new heater and try it again , if it still trips then your problem is elsewhere, if it does not trip, then it points to the new element being faulty.
If it is fan assisted make sure the fan is running o/k.
Hope this helps.
Please leave feedback.
Thanks.

Mine started doing this also. It is the "F7" error reported elsewhere, and it means a bad board or bad connections. I'm in search of a diagram or something to tell me how to open the face up and look at the contacts to the board.