Clock spring (clockspring) is a device that contains a wound up wire (ribbon cable) inside and allows the airbag, horn and steering wheel buttons to stay connected as the steering wheel is rotated to make left and right turns.
Regardless of the angle that you turn your steering wheel, you will always maintain contact between the airbag and the airbag control module.
Driver's airbag may not deploy if the SRS or airbag light is on due to due to a damaged clock spring which can result even from normal usage over time. The driver's airbag electrical circuit will trigger a high resistance fault code, potentially causing the driver's airbag to not deploy when involved in an accident.
In vehicles that have stability control or traction control, the clockspring may have an integrated steering angle sensor.
Steering angle sensor function is to determine the position of the steering wheel.
This data is used by traction control or ABS and other systems such as ESC / ESP / TCS.
The steering wheel position is reported in degrees and if you turn the steering wheel one full revolution the angle will be +/-360 degrees. 720 degrees for two steering wheel revolutions to the right and -720 for two full steering wheel revolutions to the left.
Here is a list of some of the most common problems you may experience when the clock spring fails.
Horn doesn't work
Cruise control switch does not work: On models where the cruise control in mounted on the steering wheel. If that's the case the cruise control wires are routed via the clockspring.
Steering wheel buttons don't work: Your radio or stereo may work properly but you can no longer change volume, change stations or control the radio from the steering wheel. You can no longer answer phone calls or hang up using your steering wheel buttons.
You hear rubbing noise when you turn the steering wheel: This is one of the early warning signs that the clockspring is starting to fail. Eventually, the clockspring will wear and the ribbon inside the clock spring will break.
The clockspring is located in the steering column and is mounted right underneath the steering wheel. The clock spring has wires that connect to the airbag and steering wheel buttons and on the opposite side has an electrical wire harness plugged into it.
Typical cost to replace a clock spring can range from $500-$1200. To save money replace the clock spring yourself.
You can buy a replacement clockspring for most cars online. Replacing the clock spring is a simple procedure.
For most cars, you can find a new clock spring in the $80-$250 range.
In most cases, you can also install a used clock spring without any issue.
The following video series shows you how to replace the clock spring on a vehicle. Note that these instructions vary depending on the make and model.
Remeber to always disconnect the battery and wait for 5 minutes before you start replacing or disconnecting airbag restraint system components.
Once the clockspring has been replaced, you may need to clear the codes from the airbag module if your SRS/airbag was on.
The last step is to install the clock spring. Make sure the wheels are pointed straight forward before you remove the old clock spring. Find the neutral (center) position of the clock spring. You can do this by turning the clock spring all the way to the left and stop as soon as you feel slight resistance. Then turn it all the way to the right and count the total turns. Let's say you get 6 full turns. Now dive the number of turns by two. Spin the clock spring three turns back and you should be in the center.
You may need to use an OBD2 scanner such as this Foxwell Scanner Steering Angle Calibration to carry out steering angle sensor calibration if the ABS, traction control light turn on in your instrument cluster.
To diagnose the clock spring you will need a diagnostic scanner that is able to read multiple systems not just the ECU.
Most generic OBD-II scanners only read the check engine light and are not able to read airbag or steering angle sensor data.
There are a few scanners that you can buy online which cost between $150-$200 that are able to perform multi-system diagnosis.
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