Ground Event / Encounter Other / Unknown
Equipment / Tooling
After moving Aircraft from hangar spot to the gate; I was pulling away from aircraft; stopped to let my partner in tug; and then proceeded to leave gate. Had to stop because steering in the tug locked up; could not turn steering wheel. This tug is a Hybrid with drive by wire technology. I was able to regain steering by turning off tug and recycling the computer. The problem came up again some 50 feet later when I stopped again. Had this happened while towing an aircraft there would have been major damage to an aircraft as well as injury to employees.
Tug Driver reported their drive-by-wire tug lost all steering due to a malfunctioning computer.