The occupancy mat is a sensor mounted in the front passenger . The emulator simulates a situation of a person sitting in the passenger with a belt fastened. To make the emulator work you need a diagnostic tool (like for , , etc.) to remove old errors of a broken mat that are stored in the control unit. Once you connect the emulator your diagnostic tool will be to remove old errors and turn off the / warning. Unfortunately, the errors related to the safety systems are not removing automatically. Before purchase, please scan your car with a diagnostic tool to make your / warning is caused by a defective mat. These warnings can be turned on by at least 6 sensors mounted in the . The emulator solves the problem caused by a faulty mat only. The emulator will not solve your problem if a different sensor is faulty - the / warning light will still be present after connecting the emulator and removing the error present in the diagnostic tool. Name: Car Occupancy Mat Sensor Bypass Emulator Fitment Type: Direct Replacement Install Fitment: for E-Class W211 Saloon/Sedan (production years: 2004-2009) for E-Class S211 Estate (production years: 2004-2010) for C219 (production years: 2004-2010) for S-Class W221 (production years: 2005-2013) for /S-Class Coupe C216 (production years: 2006-2014) Material: plastic colour: As shown Package Contents: 1 x Car Bypass Emulator Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.