These locks are intended to help prevent children from accidentally opening the rear doors. Use them on both rear doors whenever a child rides in the rear seat of the vehicle.
If you slide the child safety lock to the lock position before closing that door, the door cannot be opened from the inside.
The door can only be opened by pulling the outside handle.

Locking, Unlocking with Door-
Lock Knob
Doors and LocksWarm Up Three Way Catalytic Converter (Wu Twc) Inspection [Mzr 2.0, Mzr 2.5]
CAUTION:
Perform the following procedures, DTC P0421:00 is indicated only.
1. Connect the M-MDS to the DLC-2.
2. Start the engine and warm it up to normal operating temperature.
3. Turn off the engine.
4. Verify that the engine compression is within the specification..
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Crankshaft Position (CKP) Sensor Inspection [Mzr 2.0, Mzr 2.5]
Visual Inspection
CAUTION:
When foreign material such as an iron chip is on the CKP sensor, it can cause
abnormal output from the sensor because of flux turbulence and adversely affect
the engine control. Be sure there is no foreign material on the CKP sensor when
replacing.
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Power Brake Unit Removal/Installation [Mzr 2.3 Disi Turbo]
CAUTION:
Once the brake switch clearance has automatically been adjusted, it cannot
be adjusted again. Therefore, replace the switch with a new one when replacing
the power brake unit or performing any procedure that changes the pedal stroke.
Secure the steering wheel using tap ...