Repairing /Replacing of Dysfunctional Module in Microwave Oven

Sometimes only the connections of microwave oven needs to be checked and fixes. This can be done by a home appliance repair technician. But at times, a specialized technical help/support is required to repair internal circuits or fix a fault. If the first level maintenance cannot rectify a fault, then a trained technician is called. If even the trained technician cannot solve the issue, then a specialized technician associated with third - party or vendor is called.
In such a case,the specialized technician removes and replaces the faulty module with a functional unit, either on the second visit or as pre-identified.
In case even the specialized technicians are unable to repair the components or fix the fault,  or if the problem is such that cannot be fixed at customer's site, then the faulty module/component is sent to the service centre. The home appliance repair technician then collects the functional module from the service centre and fixes the microwave oven at the customer's site.