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: If a Warning Light Turns On or Flashes
If any warning light turns on/flashes, take appropriate action for each light.
There is no problem if the light turns off, however if the light does not turn off
or turns on/flashes again, consult an Authorized Mazda Dealer.
The warning contents can be verified on the center display.
1. If the ...
Mazda 6 Service Manual: Cruise Control (Some models)
With cruise control, you can set and automatically maintain any speed of more
than about 25 km/h (16 mph).
WARNING
Do not use the cruise control under the following conditions: Using
the cruise control under the following conditions is dangerous and could result
in loss of vehicle control.
...