As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE REPORTED AT 4R CACP ON TAXI OUT. AIRCRAFT RETURNED TO GATE. *S/D* BOTH BACKLIGHTS ON THE SCREEN FAILED CAUSING AN OVERHEAT CONDITION AT THE INSULATION OF THE BACKLIGHTS. THE TOUCHSCREEN WAS REPLACED. NO EVIDENCE OF ACFT ELECTRICAL PROBLEMS WERE NOTED. BOEING IS SCHEDULED TO RELEASE, IN EARLY APRIL, SERVICE BULLETINS TO CORRECT THIS ISSUE.