This bulletin applies to 2014-2016 Mazda3 and Mazda6, and 2016-2017 CX-3, CX-9 and 2014-2016 CX-5 models equipped with the Smart City Brake Support System.
In certain conditions, Smart City Brake Support (SCBS) may operate unintentionally. The owner’s manual provides 7 examples:
1. Objects on the road at the entrance to a curve
2. Vehicles passing in the opposite lane while making a curve
3. Metal objects, bumps or protruding objects on the road
4. When passing through a toll gate
5. When passing under a vinyl curtain or flag
6. Plastic objects such as pylons
7. Two-wheeled vehicles, pedestrians, animals or standing trees
There may be frost/water drops on the outer surface of the windshield around the black printing portion at the upper center (where the infrared laser beam is emitted). The laser sensor light beam may be refracted by water drops or foreign material on the windshield. In this case, the laser sensor may not detect an obstruction ahead correctly. The near infrared laser beam (sending) emitted from the laser sensor (sender) is refracted by water drops on the windshield and reflects an object (i.e. a traffic sign) outside the normal sending range. The reflected beam (receiving) by the traffic sign is also reflected by water drops and received by the laser sensor (receiver). In this case, the system may detect an object outside the normal detection range as a vehicle and the SCBS may operate unintentionally.
In the case of front and/or water drops on the outer surface of the windshield, operate the wiper system to remove the front/water drops. Advise the customer to properly clean the windshield. The presence of oil films may cause rain drops to stick on the windshield. If the customer is unable to perform these preventative measures, advise the customer to torn off the SCBS operation temporarily. Note that if the SCBS operation is turned off, when the engine is re-started the system becomes operational again.