The seat occupancy mat is a sensor mounted in the front passenger seat. The emulator simulates a situation of a person sitting in the passenger seat with a seat belt fastened. To make the emulator work, you need a diagnostic tool (such as Autel, Bosch, iCarsoft, etc.) to remove old error codes from a faulty seat mat stored in the airbag control unit. Once connected, the emulator allows your diagnostic tool to clear existing errors and turn off the SRS/airbag warning light. Error codes related to safety systems do not clear automatically. Before purchase, scan your vehicle with a diagnostic tool to confirm the SRS/airbag warning is caused by a defective seat occupancy mat.Name: Car Seat Occupancy Mat Sensor SRS Bypass Emulator Fitment Type: Direct Replacement Install Condition: Type: 3+2Pin 2 Heads Fitment: for Mercedes Benz C-Class W203 Saloon/Sedan (2000-2004) before facelift Color: As Shown Material: Plastic Package Contents: 1 x Car Seat Bypass Emulator Sensor Note: Light reflection and different display settings may cause slight variations in color between the image and the actual item. Measurement may vary by +/- 1-3 cm.