1. Disconnect the liftgate lock actuator connector.
2. Apply battery positive voltage to the liftgate lock actuator terminals and inspect the operation of the liftgate lock actuator.


Trunk lid lock actuator inspection
Door lock timer unit removal/installationMazda 6 Service Manual: To Resume Cruising Speed at More Than 25 km/h (16 mph)
If some other method besides the OFF/ CANCEL switch was used to cancel cruising
speed (such as applying the brake pedal) and the system is still activated, the
most recent set speed will automatically resume when the RESUME/
switch is pressed.
If vehicle speed is below 25 km/h (16 mph), incre ...
Mazda 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.
...