Occupant Restraint Controller (ORC)

Occupant Restraint Controller (ORC)

The occupant restraint controller (ORC) is a complex electronic device that manages the operation of your vehicle’s airbags, seat belt pre-tensioners and other restraint system components found in your car or truck. Depending on the make and model of your vehicle, the ORC can have a different name, including SRS (supplemental restraint system) control module, airbag control module, airbag ECU, sensing diagnostic module, restraint control module or sophisticated airbag sensor module. Regardless of its name, the device performs the same function, keeping your restraint system ready for an emergency.

Your occupant restraint controller is a type of computer that monitors and operates your restraint system components. It relies on an array of different sensors located in the front of your vehicle, in your door pillars, door beams or some other places around the vehicle. The controller can be found under one of your front seats or under the center console or the dashboard. Wherever it is located, your ORC comes into play each time you rotate the ignition key into the run position or push the start button. 

Based on the data received from the sensors, the occupant restraint controller operates the airbags, door locks and emergency lights to save your life in the event of a road collision. Depending on the information provided by a specific sensor, the module decides which airbag should be inflated if there is an emergency. The full range of restraint system components it can operate includes driver and passenger airbags, knee airbags, side-impact and side curtain airbags, seat belt pre-tensioners, door locks, emergency lights and even your fuel pump.

The occupant restraint controller not only monitors and operates the airbags and other components, but also records and stores accident-related information if an accident happens. It usually records data that last up to twenty seconds before a collision, which makes it possible to reconstruct the accident. This can come in handy for technicians who work on repairing the vehicle after a collision, and insurance carrier personnel who try to determine the cause of the accident. In most cases, they can be provided with the vehicle speed, use of the seatbelts, throttle position and brake usage.

An occupant restraint controller is a maintenance-free device that doesn’t alert of any problem when all restraint system components perform as they should. Each time you turn the ignition key, it starts a self-diagnostic process to make sure everything functions properly. If any problem is detected, the ORC will turn on the warning light on your dashboard. If so, that should be addressed as soon as possible to prevent serious injuries in the event of an accident. Driving a vehicle with illuminated warning lights is not recommended for safety reasons.

Signs that your occupant restraint controller is failing 

Any problem detected by your occupant restraint controller will cause the airbag/SRS warning light on your dashboard to come on. This will also deactivate your airbags until the fix is done. The source of the problem can be the module itself or a failure of a restraint system component. Here are the most common problems that lead to the illuminated warning light:

  • Worn-out or damaged ORC wiring
  • Short circuits within the ORC or the entire system 
  • ORC software errors
  • Bad electrical connectors
  • Dust or water inside the ORC
  • Physical damage to the occupant restraint controller

Occupant restraint controller replacement

If your ORC is damaged or faulty the only way to fix the problem is a replacement unit. A repair facility or mechanic will need to disconnect the module from the systems and to replace it with a brand-new unit that should run the same software as your original one. When installed, it must be tested to make sure the restraint system is properly functioning.

We do not recommend you to replace the controller yourself. It operates and manages explosive devices that you might damage or activate when working on the restraint system. The vehicle must be powered down to prevent airbag firing or explosions. Besides, you will need specific diagnostic equipment to do troubleshooting.