Airbag inspection made easy

When a fault appears in the SRS (Supplemental Restraint System), a warning light will appear on the dashboard.

When the ignition is switched on, the SRS control unit (ECU) will check communication with all the airbag units around the vehicle, the trigger mechanism and seat belt tensioners etc. If communication is satisfied then the light will extinguish,

However, if the return signal from one of the units is not received, or it picks up information that is out of the expected range, then the light will remain on.

There is a wide range of error codes that can be received by the SRS ECU, the number depending on the vehicle you have. However there are a few common ones that can trigger it.

• Steering Wheel Clock Spring; This is the ribbon mechanism which is behind the steering wheel that contains the wires to the drivers airbag. Like a clock spring, they wind and unwind as the steering wheel turns and whilst fairly flexible, after a time they can become brittle and crack
• Under Seat Connection; There is a connector block under the front seats that connects the wires in the seat SRS components to the vehicles wiring loom. These have to be flexible as the seat needs to be adjusted for position of the occupant and over time they can work loose, especially on 3 door vehicles where the seat are pushed forward to allow access for the rear passengers.

Whilst there is little you can do to avoid simple wear and tear or component age, there are a few things that you can do to avoid some issues

• Do not allow rubbish to accumulate behind the front seats. This rubbish can go under the seats and dislodge the seat connections.
• When moving the front seats for position, try to do so gently without slamming them forward and back.
• If you have a 3 door and the seats fold forward to allow access for the rear passengers, try to fold the seats with some due care.

Issues are more common with age, but also with more and more complex and numerous airbags within the car, there are undoubtedly more issues to occur.

• The mechanic will plug into the SRS system though your vehicle's diagnostic port.
• They will then scan the system for the error code.
• Once a list of the codes has been identified and recorded, they will clear the codes and retest.
• The remaining error codes will then dictate the next course of action
• If there are communication error codes, where possible, the mechanic will check the connections.
• If the connections are fine, then the mechanic will quote you on the required repairs.
• If the SRS light remains off after the clearing of the codes, it may have been a temporary fault in which no additional action needs to be taken.

The cost of an SRS Fault Diagnostic depends on your car and your area. Find out what you could save by having the diagnostic test by ClickMechanic, by selecting your car at the top of this page!