Initial request for service. Once their service engineer visits and confirms that the parts needed for the service are not available, they will offer you the compensation (please tell them to service your TV at any cost, else they may say that the customer does not wants service and may close the request), provided you can provide the original invoice. They says that typically they were supposed to provide service and spares for 7 years. So if the TV conks off within 7 years from purchase date, then only it will be considered. Not sure about the basis of calculation of quantum of compensation. They offered me 50% for a 4.5 years old plasma. I simply accepted it. My TV actually costed me 65K, but the invoice was 76500/-. I got 38250/- back. So essentially I lost 27K only in the bargain.
In fact, that precisely is the reason, there is no point buying expensive extended warranty. In most cases, after 2-3 years, they simply can't service the TV, as the spares for new TV is different from earlier gen. For most of the premium brand they offers similar compensation (the key is to have the original invoice) and also to request for service from their authorised service centres.