C0628 indicates a performance fault in the Variable Effort Steering (VES) module, which controls the level of electric assist provided to the steering system. The PCM has detected that the module is not delivering the expected torque or response characteristics.
The electric motor or hydraulic actuator that provides assist may have internal wear, a shorted winding, or mechanical binding, preventing proper torque output.
Corrosion, broken pins, or high resistance in the harness can cause erratic signals between the steering module and the PCM.
A malfunctioning sensor can send inaccurate data, causing the module to miscalculate the required assist level.
Insufficient fluid pressure or debris can impede the hydraulic assist mechanism, triggering the performance fault.
Only after ruling out hardware issues should a rare communication problem within the PCM be considered, as it is an unlikely root cause.
It is possible but very rare. In most cases the fault lies in the steering motor, sensor, wiring, or fluid system. Replacing the PCM should be a last resort after all other components have been verified.
If the underlying fault remains, the code will likely return and the steering symptoms will persist. Clearing the code only resets the monitor temporarily.
The vehicle will usually remain drivable, but reduced steering assist can make low‑speed maneuvering difficult and may increase driver fatigue. Repair is recommended promptly.
Not necessarily. Often a single faulty sensor, a bad connector, or a worn motor can be repaired or replaced without discarding the whole module.