Per the 1900 Series Data Sheet:
Warranty Information
The Cisco 1900 Series Integrated Services Router have a 1 year limited liability warranty.
By the way this forum is dedicated to the Cisco Small Business routers, not really the best forum for the ISR routers. The best Support Forum for all Traditional Cisco products is the Cisco Netpro Support Forum (Netpro link at the near the top of this page).
Best Regards,
Glenn