1. Disconnect the back-up light switch connector.
2. Inspect for continuity between the back-up light switch terminals using an ohmmeter.


Back-up light switch removal/installation
Flasher unit removal/installationMazda 6 Service Manual: Immobilizer System
The immobilizer system allows the engine to start only with a key the system
recognizes.
If someone attempts to start the engine with an unrecognized key, the engine
will not start, thereby helping to prevent vehicle theft.
If you have a problem with the immobilizer system or the key, consult ...
Mazda 6 Service Manual: Forward Sensing Camera (FSC) (Some models)
Your vehicle is equipped with a Forward Sensing Camera (FSC). The Forward Sensing
Camera (FSC) is positioned near the rearview mirror and used by the following systems.
High Beam Control System (HBC)
Lane-keep Assist System (LAS) & Lane Departure Warning System (LDWS)
Traffic Sign Reco ...