As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WX RADAR SHOWS FALSE RETURNS AT 9 & 3 O'CLOCK POSITIONS WITH AUTO SELECTED OR DESELECTED. GROUNDED - YES. PERFORMED WEATHER RADAR SYSTEM OPS CHECK, OPS CHECKED GOOD. NO FALSE/ERRONOUS RETURNS NOTED. REF B737-800 AMM 34-43-00-710-802-001 AND AMM 34-43-00730-802-001.