As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI OUT SAW ALL 3 ZONE TEMP LIGHTS HAD ILLUMINATED WITH NO ASSOCIATED MASTER CAUTION. ALL 3 RESET WITH PUSH TO RESET. NO CONTROL OVER ANY TEMPERATURES. ACFT GROUNDED. BOTH ZONE TEMP CONTROLLERS FAULTED CABIN ZONE AND FLT DECK SELECTOR FAULTS. ACCOMPLISHED TEST MULTIPLE TIMES. R & R TEMP CONTROL MODULE REF MM 21-61-15, OPS CHECK NORMAL.