Is my navigation system covered by the warranty when parts are not available in the US?
The warranty terms will govern the obligations of the company. Typically, a warranty will state that if a replacement component is no longer available or is discontinued, the company reserves the right to substitute the component for an equivalent item, or offer an upgrade option. If any lost or damaged parts are no longer available, your insurance company could also offer to pay you an amount equal to the cost shown in the manufacturer's latest price guide.
In some cases, a party may claim impossibility as a defense to performing their obligation under the contract. To be successful, it must be shown that the party raising the defense didn't create the impossibility and couldn't have foreseen the situation. However, it is common for warranties foresee and address what the company will do in the event a replacement part is no longer available.
The buyer's right to require repair is subject to the unreasonableness of the costs or the trouble caused to the seller. The seller's obligation to repair depends, for example, on his technical and human resources. If he lacks the technology, skill, or personnel, or if procuring spare-parts and other equipment needed would become very expensive, the seller may be excused.