As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAKEOFF ROLL, THE FIRST OFFICER DID NOT RECEIVE ANY RESPONSE FROM THE RUDDER PEDALS OR THE STEERING TILLER. TAKEOFF WAS ABORTED AT SLOW SPEED. AIRCRAFT RETURNED TO GATE WHERE MAINTENANCE REPLACED THE BRAKE STEERING CONTROL UNIT. OPERATIONAL CHECK OK.