The sensors make a clicking noise when they are working. Put your ear up to the bumper and if one doesn't make the noise it is bad or the connection is loose.
2014 Carrera 2S
- White/2 Tone Espresso/Cognac - Aerokit - PSE - PDCC - SPASM - PDK - Sport Chrono - 20" wheels w/OEM Spacers - Glass Roof - Leather Dash - way too much more to list
2013 F12 M6
- Alpine White/Black Merino - Executive - LEDs - B&O - DA - Lots more
2013 E92 M3
- LeMans Blue/Black Novillo -(Lease ended need new signature pic)