As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WEATHER RADAR SHOWING FALSE RETURN +_ 3 DEGREE EITHER SIDE OF AIRCRAFT TRACK EXTENDS APPROXIMATELY 60 MILES ON NAV DISPLAY. GROUNDED - YES. PERFORMED WXR RADAR SYSTEM BITE PROCEDURE NO FAULT NOTED B737-900 FIM 34-43 TASK 801, WXR RADAR SYSTEM OPS TEST PASSED B737-900 AMM 34-43-00-710-802-001, UNABLE TO DUPLICATE DEFECT.