As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 6379 - IAD-SYR - DURING TAXI, AIRCRAFT RETURNED TO GATE DUE TO CAPTAINS VSI/TCAS DISPLAY WENT BLANK. MAINTENANCE INSPECTED AND COMPLETED FUNCTIONAL CHECK. NO DEFECTS NOTED AND COULD NOT DUPLICATE PROBLEM. OPS CHECK OK. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)