Theory Of Operation

WARNING: This page is about a different car, the 2015 Fiat 500. However, it is still accessible from the selected car via links, so may be relevant.

When powered, the Occupant Restraint Controller (ORC) sends a test current across the Driver Seat Belt Buckle Switch circuits to verify the integrity of the switch and wiring. The front seat belt switches cannot be adjusted or repaired and, if ineffective or damaged, the entire front seat belt buckle-half unit must be replaced. The seatbelt reminder lamp will display in the instrument cluster for this fault. The ORC obtains the buckle switch status of the driver and front passenger, as well as the status of the front passenger seat occupant detection mat. If the driver or front passenger is unbelted, the ORC sends a message to the IPC over the CAN-B bus to turn on the seatbelt reminder light. The light remains on until the front seatbelts are fastened. An audible alert triggers within 60 seconds of vehicle speed over 5 mph. The seatbelt reminder light remains illuminated until the front belts are fastened. The seatbelt buckle switch consists of a Hall-effect sensor assembly. The ORC determines the status of the seatbelt (buckled/unbuckled) based on the amount of current drawn by the sensor. When the seatbelt is unbuckled, the sensor draws a current of approximately 6.5 mA. When the seat is buckled, the sensor draws a current of approximately 15 mA.