As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BTB - AFTER ENG START UNABLE TO TURN STEERING TO RT. STEERING WAS JAMMED ONLY TO RT SIDE. AFTER INSPECTION BY MAINT JAM WAS NOT REMAINING AND WERE ABLE TO RETURN TO GATE. FOUND NLG STEERING BYPASS LEVER PIVOT BOLT LOOSE. RESECURED AND RESAFETIED BOLT. CHECKED STEERING, FULL DEFLECTION LT AND RT. OK.