As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER PUSH, FO FD AMBER FLAG ILLUMINATED ALONG WITH MCP ALTITUDE GOING TO 50,000 AND COULD NOT BE MOVED. AFTER ENGINE START TO TAXI BACK IN, CONDITIONS RETURNED TO NORMAL. GROUNDED - YES. ELEC PWR SWITCHOVER - DFCS NO FAULT/FAULT HISTORY - DFCS AND FMCS R-T-S TESTS PASSED B737-800 AMM 22-11-00.