Plenty of problems to solve with electric cookers!
Heating elements: The most common problem is the failure of a heating element.
On the hob, there a 4 different types of heater.
The standard coiled element; the solid plate; the ceramic; the halogen.
Any of these can be replaced.
One way to determine if the heater is at fault, rather than the switch which operates it, is to by-pass the switch. Unless you are very competent, it is wise to leave this to a professional.
Switches (simmerstats) can be replaced.
A fault will often be indicated by the ring not going completely cold when switched off. This will mean that the switch is "leaking" current to the element.
In the oven, the oven elements, or grill elements can also be replaced.
Timers also fail. They normally simply stop working.
For further help with repairs, try www.howtomendit.com