Clock Springs / Spiral Cables
What are Clock Springs?
In a vehicle steering system Clock Spring Spiral Cables are a round shaped connector. It allows a steering wheel to turn, whilst still keeping the electrical circuit connected between the wheel and the rest of the vehicle’s electric system. This allows the horn, airbag and other devices on the steering wheel, such as audio controls and cruise control to function regardless of the steering wheel’s position.
How do Clock Springs work?
Clock Springs have a ribbon cable (often called a spiral cable) inside a circular unit. The word “spring” is not strictly accurate. The coiled ribbon cable does not function as a spring in any way. The unit housing the cable has 2 parts that can rotate within itself. This allows the long ribbon cable to wind and unwind itself as the wheel is turned back and forth. Thus the electrical connection is kept through the cable regardless of steering wheel position and wheel movement. There is a limit to the number of turns that a unit can make based on full lock-to-lock of the vehicle’s steering wheel. This is usually around 5 turns. The length of the wound cable inside is limited to allow just that many turns. As such, failure to correctly centre a clock spring at installation may leave too little cable length wound up. So when the wheel is moved to lock on one side the cable will reach its end and be snapped inside the unit, creating complete circuit failure.