What does it mean when the EPS light is on and the steering wheel won't turn?
2 Answers
When the EPS light is on and the steering wheel won't turn, it indicates a fault in the Electric Power Steering system. In such cases, it is not recommended for the vehicle owner to attempt repairs themselves. Instead, they should promptly visit a professional repair shop to have the fault data read with a diagnostic tool for targeted repairs. The Electric Power Steering system is a power steering system that directly relies on an electric motor to provide auxiliary torque. It mainly consists of components such as a torque sensor, vehicle speed sensor, electric motor, reduction mechanism, and electronic control unit. The basic principle of the Electric Power Steering system is as follows: the torque sensor is connected to the steering shaft (pinion shaft). When the steering shaft rotates, the torque sensor begins to work, converting the relative angular displacement generated between the input and output shafts under the torsion bar's effect into an electrical signal, which is then transmitted to the ECU. The ECU determines the motor's rotation direction and the magnitude of the assist current based on signals from the vehicle speed sensor and torque sensor, thereby achieving real-time control of the power steering.
I remember last time my car had the issue of the EPS light coming on and the steering wheel locking up. It happened while I was driving on the highway. Suddenly, the EPS light came on, and the steering wheel became as hard as a rock, almost impossible to turn. I quickly turned on the hazard lights and slowly pulled over to the side. After restarting the engine, the situation didn’t improve, so I checked the user manual. The manual said this could be caused by a blown fuse or a sensor malfunction. I went to the engine compartment to check the fuse box and indeed found the relevant fuse had melted. After replacing it, the problem was resolved. Normally, if you notice abnormal noises in the steering system or frequent light flickering while driving, you should pay attention, as delaying repairs could lead to more serious damage to the steering system. In such cases, it’s best not to force the drive to avoid accident risks. It’s recommended to have a technician perform a comprehensive inspection during every maintenance service.
