1. Remove the climate control unit.
2. Inspect for continuity between the fan switch terminals using an ohmmeter.
Mazda 6 Service Manual: Lane Departure Warning
If the system determines that the vehicle may deviate from its lane, the lane
departure warning (beep sound, rumble sound*1, or steering wheel vibration) is activated
and the direction in which the system determines that the vehicle may deviate is
indicated in the multi-information display and ...
Mazda 6 Service Manual: Anti-theft system
Alarm Conditions
If the anti-theft system protection has been activated, any one of the
following conditions will trigger the system:
- Disconnected battery cable
- Discharged battery
- Disconnected audio unit connectors
If the system is triggered, the audio unit will then be ...