The 6 most common part(s) or condition(s) which cause the symptom Oven won't turn on are listed below starting with the most likely. Check or test each item and watch any available videos.
RepairClinic Item # 784603
Even though the oven igniter may be glowing, it may be too weak to allow the gas valve to open. If the oven won't turn on and the oven igniter glows for more than 90 seconds without igniting the gas flame, the oven igniter should be replaced. This is the most common part that fails when the oven won't turn on.
Although not as common, if the oven won't turn on it is possible that the appliance is not receiving proper voltage. Electric ovens require 220 volts of alternating current. If for some reason the appliance is receiving significantly less, the oven won't turn on. Check for proper voltage using a volt meter at the socket where the appliance plugs in.
RepairClinic Item # 1066375
The oven control board has a set of relays that turn on and off power to the bake and broil circuits according to the customer settings and sensor input. If the oven won't turn on the problem is usually with the heating components. However, if the oven control board is bad, it might not send voltage to the heating components. To determine why the oven won't turn on, first test the simpler components in the circuit. If no power is present at the proper terminals on the control board, the control board will need to be replaced.
RepairClinic Item # 905772
Although not as common, if the oven won't turn on the thermal fuse may have blown. The thermal fuse is designed to protect the appliance and help to prevent a fire. If the oven gets too hot, this fuse trips. The thermal fuse is not resettable and will have to be replaced. It can be checked for continuity. If it has continuity, it's OK. Not all ovens have a thermal fuse.
If the oven won't turn on, there might be a burnt wire supplying power to the bake element. Sometimes the wire supplying power to the element burns out right near the element itself. Check for this by just looking at the wires leading to the element. If they're burned out it is usually easy to spot.
RepairClinic Item # 1182155
The oven safety valve works with the oven igniter to provide gas to the burner. If the oven won't turn on it is possible that the oven safety valve is defective. However, this is very rare. Most often, the oven igniter is too weak to allow the oven safety valve to open. If the oven won't turn on, check the igniter first.