What was found
ENROUTE, WEATER RADAR SHOWS LARGE NUMBER OF RETURNS AT 160-120 NM. AS WE APPROACH THEY WOULD DISAPPEAR. WX RADAR GAIN WAS SET TO NORMAL ON BOTH SIDES AUTO ON WX+T ON BOTH SIDES. WX TEST DID NOT APPEAR TO WORK AND DISPLAYED WX FAIL AND PWS FAIL AFTER THE TEST. GROUNDED - YES. ACCOMPLISHED WXR SYTEM OPS TEST, TEST PASS. REPLACED WXR R/T WITH SERVICEABLE ONE. DID NOT DISCONNECT ADM. ACCOMPLISHED WXR SYTEM OPS TEST, TEST PASSES. REF B737-900 AMM 34-43-41-400-801 & 34-43-00-710-802-001. A/C REQUIRES FIRST 60-MINUTES OF ETOPS REVENUE FLT TO VERIFY WXR OPS NORMAL IN FLIGHT. VERIFICATION FLIGHT UNSATISFACTORY REF L/P 11581047. THIS CLEARS FVR DEFERRAL.