As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CONT CAB ZONE TEMP LIGHT ON RECALL, LIGHT EXTINGUISHES WHEN MASTER CAUTION IS PUSHED. GROUNDED - YES. PERFORMED B737-900 FIM 21-62 TASK 842. RESET FAULT AND LIGHT STAYS EXTINGUISHED. PERFORMED MULTIPLE OPS CHECKS OF CAB ZONE TEMP CONTROLLER PER B737-900 AMM 21-61-00-700-807-002. NO FAULTS FOUND. COULD NOT DUPLICATE PROBLEM.