National Assessing & Engineering

Occupant Classification System Recalibration

Are Your Passengers Safe? Here Is Why Occupant Classification Systems Need Recalibration

Passenger airbags are a common sight in cars now, having been installed in all new cars for some time. With the passenger airbag comes the system to detect whether there is a passenger sitting in the seat, and therefore whether the airbag needs to deploy in an accident.

Occupant Classification System Recalibration

These systems are known as Occupant Classification Systems (OCS), but can also be called Passenger Weight Systems (PWS), Occupant Detection Systems (ODS) and Seat Occupant Sensors (SOS). These systems are in every vehicle that is made today, and their job is to detect if a passenger is sitting in the passenger seat. Along with this, they also detect the passenger’s approximate weight and seating position. This information then allows the side airbag to deploy correctly relative to the person sitting in the seat.

By this point it’s probably pretty clear how an uncalibrated system could be potentially dangerous. If the system is not properly calibrated, the airbag may not deploy at all, or may deploy incorrectly, resulting in serious injury or even death.

What may not be as obvious is when exactly these systems needs to be recalibrated.

No matter how big the accident or how much damage it caused, the Occupant Classification System should always be checked and recalibrated after any accident, including if no one was in the passenger seat. Toyota, for example, states that any vehicle involved in an accident or collision could have Diagnostic Trouble Codes set, regardless if there was a passenger in the seat or not, and that any vehicle with collision damage must have the Occupant Classification System recalibrated.

If the passenger seat is removed from the vehicle, the system will also need to be recalibrated once the seat has been reinstalled. The seat may need to be removed for a number of repairs including b-pillar damage repair, floor damage repairs and dashboard replacements. Whatever the case, the system must be recalibrated when the seat is put back in the car.

If you have had a car repaired after an accident, it is absolutely critical to have the Occupant Classification System checked and recalibrated for the safety of your passengers. We at NAQ ensure this is checked as part of our post-repair assessment. If you want to make sure your car was repaired properly, give us a call now on 1800 844 999 or email us on