As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE PERFORMING PACK ZONE TEMP CONTROLLER BITE DURING ACM INSTALL ON LOGPG 12131232, THE #1 ZONE TEMP CONTROLLER FAULTED THE SRADA EXIT LIGHT FOR THE L/H PACK. GROUNDED - YES. ACCOMPLISHED B737-900 FIM 21-62 TASK 853 SRADA EXIT LIGHT EXTINGUISHED. PERFORMED PACK ZONE TEMPERATURE CONTROLLER BITE PER FIM 21-62 TASK 801 BITE TEST PASSED WITH NO FAULT LIGHTS ON BOTH CONTROLLERS.