Inspect the PCM. (See PCM INSPECTION.)
Solenoid valve removal/installation
Pcm removal/installationMazda 6 Service Manual: Locking, Unlocking with Door- Lock Knob
Operation from inside
To lock any door from the inside, press the door-lock knob.
To unlock, pull it outward. This does not operate the other door locks.
NOTE
The red indication can be seen when the door-lock knob is unlocked.
Operation from outside
To lock the rear and front passenger doo ...
Mazda 6 Service Manual: Rear door lock actuator inspection
Door Lock Actuator
1. Disconnect the front door lock actuator connector.
2. Apply battery positive voltage to the front door lock actuator terminals
and inspect the operation of the front door lock actuator.
If not as specified, replace the front door lock actuator.
With double locking ...