What was found
AFTER ENGINE START ON RECALL, #1 PACK ILLUMINATED ON RECALL. EXTINGUISHED ON RESET. GROUNDED - YES. RELEASED PER MEL 21-32B LEFT PACK LIGHT ILLUMINATED ON RECALL. ENROUTE MEL - A/C CKD & REL IAW MEL 21-32B, LEFT PACK ONE TEMP CONT SYS INOP. PERFORMED PACK TEMPERATURE CONTROL BITE PROCEDURE B737-900 FIM 21-62 TASK 801. NO FAULTS & PERFORMED FIM 21-62 TASK 802. AFTER PERFORM PZTC TEST REF B737-900 AMM 21-62- TASK SUPPORT SHOW TCV FAULT AT PACK #1. ACCOMPLISHED BITE CHECK ON BOTH PZTC PER AMM 21-61-00-740-801-002. LH PZTC SHOWS ACTIVE FAULT FOR LH PACK TCV. ACCOMPLISHED B737-900 FIM 21-62 TASK 830. NO DISCREPANCIES FOUND. DUE TO HISTORY REPLACED LH TCV PRECAUTIONARY PER AMM 21-51-10. PZTC BITE AND GROUND TEST SUCCESSFUL. LEAK CHECK GOOD. THIS CLEARS MEL 21-32B.