Q: I purchased an item, but did not open it until after the manufacturer’s warranty expired. It was defective. Can I demand a refund from the store owner?
A: A person who sells an item that is liable to be defective should check that it is intact. This is included in the prohibition against onaah. In principle, a defective item can be returned even if the defect is discovered years later (Prishah 228:5; Nesivos 60:4; C.M. 232:3).
Nonetheless, it is known that one who buys with intention to resell (sarsur) does not check the merchandise. Therefore, it is the customer’s responsibility to check if there is a defect.
If the customer did not check the item and there was a loss, whereas had he checked earlier and could have returned the item to the manufacturer before the warranty expired, the seller is believed that he was unaware of the defect, and the loss is the customer’s (C.M. 232:18).
In any case, the common commercial practice is to follow the warranty terms.