As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE PERFORMING ASA T/C 78273000, #1 ENGINE HAS SHORT TIME FAULT 73-30311 THE START SWITCH SIGNAL AND ARINC BUS DATA DISAGREE, FAULT SET IN PREVIOUS 10 LEGS. GROUNDED - YES. VERIFIED ACTIVE ENG. NO. 1 FAULTS 73-30311 AND 73-20771. REPLACED NO. 1 ENG. EEC REF B737-900 AMM 73-21-60.