1. Remove the rear door unit.
2. Remove the screws, then remove the rear door latch and lock actuator.

3. Install in the reverse order of removal.
Front door latch and lock actuator removal/installation
Front door key cylinder removal/installationMazda 6 Service Manual: Dtc b1318
Caution
When attaching the tester lead to the ABS (ABS/TCS) HU/CM harness
connector, the SST (49 G066 001) must be used. (See ABS (ABS/TCS) HU/CM
INSPECTION.)
Diagnostic procedure
...
Mazda 6 Service Manual: Interior Care
WARNING
Do not spray water into the vehicle cabin: Spraying water into the
vehicle cabin is dangerous as electrical devices such as the audio and switches
could get wet resulting in a malfunction or vehicle fire.
NOTE
Do not wipe the interior using alcohol, chlorine bleach, or organic solv ...