What causes the Audi A6 steering wheel to become immobile and display a steering failure?

[MacAngela]

Audi A6 steering failure and immobile steering wheel causes: 1. Steering gear failure. 2. Steering gear power supply failure and steering gear grounding failure. 3. Mechanical causes of heavy steering mainly include steering joint jamming, severe lack of lubrication, wear or even burning of steering column and bushings, which can all lead to heavy steering. 4. Chassis suspension system failure (lack of lubrication and rusting of steering tie rod and drag link joints). Additional information: 1. When steering gear power supply and grounding fail: the computer diagnostic system cannot recognize the power steering unit. 2. When steering gear power supply and grounding intermittently fail: the computer diagnostic system can read the power steering unit, the power steering unit shows no fault records, while other control units communicating with the power steering have related records.