1. Disconnect the negative battery cable.
2. Remove the headlight cleaner switch. (See HEADLIGHT CLEANER SWITCH REMOVAL/INSTALLATION)
3. Inspect for continuity between the headlight cleaner switch terminals using an ohmmeter.


Headlight cleaner switch removal/installationMazda 6 Service Manual: Cargo compartment light switch inspection
1. Remove the liftgate lower trim. (See LIFTGATE LOWER TRIM
REMOVAL/INSTALLATION)
2. Disconnect the cargo compartment light switch connector.
3. Inspect for continuity between the cargo compartment light switch
terminals using an ohmmeter.
If not as specified, replace the liftgate lock.
...
Mazda 6 Service Manual: Rear drain hose installation
Caution
If the rear drain hose is pinched or bent anywhere, the water in the hose may
not discharge and enter the inside of the vehicle. During and after installation
of the trims and the headliner, always make sure there is no interference with
the rear drain hose. Fix any problem if foun ...