As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
#1 ENG S/N 896974 HAS LONG TIME FAULT 73-20171 "INTERNAL EEC FAULT". DEFERRED PER T/C 78273000. GROUNDED - YES. REMOVED AND REPLACED EEC ON #1 ENGINE PER AMM 73-21-60/401, OPERATIONAL TEST PASSED. NO FAULTS FOUND GROUND VERIFICATION SUCCESSFUL.