As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PREFLIGHT INSPECTION, THE ACM OVERHEAT ANNUNCIATOR ILLUMINATED WHILE APU WAS RUNNING. E6/E5 FAULT CODE ON TEMPERATURE CONTROLLER. SMOKE IN COCKPIT OBSERVED. MAINTENANCE TROUBLESHOT THE DISCREPANCY TO A FAULTY RIGHT COCKPIT TEMPERATURE CONTROL VALVE. INSPECTED DUCTS AND WIGGINS CLAMPS FOR LEAKS. NONE NOTED. OPERATIONAL CHECKS COMPLIED WITH. AIRCRAFT WAS RETURNED TO SERVICE.