What was found
LEFT PACK CAUTION LIGHT ON DURING CRUISE AT FL 360. RAN QRH AND PACK LIGHT WENT OFF, BUT ILLUMINATES W/RECALL ROUGHLY 10 MIN LATER RECEIVED LT PACK CAUTION LIGHT AGAIN. CAUTION CLEARED AGAIN AFTER QRH. GROUNDED-YES. VERIFIED FAULT, ACCOMPLISHED PACK TEMP CONT BITE NR 2 CONT NO FAULTS. NR 1 CONT SHOWS (SRADA) EXIT FAULT. ACCOMPLISHED BITE RESET. ACCOMPLISHED RAM AIR MODULATION SYSTEM TEST, TEST PASS. REACCOMPLISHED PACK TEMP CONT BITE TEST, TEST PASS NO FAULTS. RAN BOTH PACKS FOR 40 MIN, NO PACK LIGHT ILLUMINATES, REF B737-900 M/M 21-51-00-730-801, 36-00-00-860-801 & B737-900 FIM 21-62 TASK 801 & 21-62 TASK 853.