In the US, when we are issued a passport with a RFID tag, the passport comes with a flier stating that even if the chip is unreadable, the passport's validity is not affected. I would imagine this applies to non-US passports, provided the machine-readable portion of the identity page is still readable. The chip is not "the passport" it is a part of the actual document that makes the document easier to process. What matters is the information on your passport, and that's not affected by the chip or lack thereof.