As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 7620 IND TO ORD, ON TAKEOFF ROLL DURING THE INITIAL ACCELERATION THE COCKPIT DOOR SWUNG OPEN. CREW ABORTED TAKEOFF. COCKPIT DOOR WAS PREVIOUSLY DEFERRED TO MANUAL MODE DUE TO AN INOPERATIVE ELECTRIC LOCKING MECHANISM. THE CREW CONTACTED DISPATCH AND AGREED THAT THE DOOR SEEMED TO BE WORKING PROPERLY AT THAT TIME AND DECIDED TO CONTINUE. RON MAINT CLEANED AND LUBED, OPS CHECK GOOD AND CLEARED MEL.