What was found
AIRCRAFT RETURNED OF FLIGHT DUE TO DURING CLIMB, THE CONFIGURATION ALARM WAS ACTIVE, TAKEOFF CONFIGURATION LIGHT TURNED ON & TAKEOFF WARNING HORN SOUNDED. PERFORMED TAKEOFF WARNING SYS TEST IAW AMM 31-51-00-730-803, DETECTING THE CB CO1398 FAILED. CB CO1398 WAS REPLACED IAW AMM 20-60-01, FIM 32-09 TASK 810 & FIM 31-51 TASK 801 PROCEDURES & TAKEOFF WARNING SYS TEST IAW AMM 31-51-00-730-803, TESTED CORRECT. AS A PRECAUTIONARY ACTION, THE PROXIMITY SENSOR WAS REPLACED IAW AMM 27-62-61-000-801. ADJUSTED & FUNCTIONAL TESTS WERE PERFORMED IAW AMM 27-62-00-820-803 & AMM 31-51-00, TESTED CORRECT.