What was found
DFW - FLT 152 - DURING FLT TO STL, LOST WEATHER RADAR. RECEIVED "ANT FAIL" MSG OCCURRED DURING CLOUDY WEATHER CONDITIONS. DIVERTED TO DFW WHERE MAINTENANCE REMOVED AND REPLACED WEATHER RADAR PEDESTAL DRIVE UNIT IAW AMERICA WEST AIRLINES TASK CARD R1A34003. OPERATIONAL CHECK WAS GOOD IAW AMERICA WEST AIRLINES TASK CARD A1B34036. TEAR DOWN REPORT CONFIMS FAILURE OF THE PEDISTAL DRIVE UNIT. UNIT FAILED BENCH TEST, THE AZIMUTH GEAR NEEDED TO BE REPLACED. REPLACED DEFECTIVE PARTS AND OVERHAULED UNIT IAW CMM 34-45-22 REV. 17.