As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTO THROTTLES DISCONNECTED IN DESCENT W/RED AUTO THRUST LIGHT. TRIED TO REENGAGE, DID NOT WORK. "RETARD" STILL DISPLAYED ON FMA. GROUNDED - YES. REMOVED AND REPLACED FCC-AA. OPS TEST GOOD. ALL REQUIRED TESTS PASSED. REF B737-900 AMM 22-11-33.