As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT RETURNED TO GATE DUE TO THE LEFT ENGINE AT START AN CONTROL LIGHT TURNED ILLUMINATED. PERFORMED A BITE TO THE LEFT EEC IAW AMM 73-21-00, SHOWING FAILURE CODE 73-31481. THE LEFT REVERSER SLEEVE POSITION SIGNAL OUT OF RANGE. THE LEFT REVERSER ACTUATOR WAS REPLACED IAW AMM 73-31-03, TESTED CORRECT.