As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIGHT AFTER TAKEOFF TANK NR 1 SHOWED 0. 20 MIN LATER AT FL 360 BOTH TANKS SHOWED DASHES. THE GAUGES CAME BACK & WORKED AS WELL AS WE COULD TELL. DID NOT START GOING TO DASHES AGAIN UNTIL ENG SHUT DOWN. VERIFIED NO FAULT CODES ON FCU MEMORY. R & R SYS POWER SWITCH S7199 IAW AMM CH 20-13-04, OPERATIONS CHECKED OK IAW AMM CH 28-23-08 AND 28-41-00.