Purpose/Function
With the adoption of the master cylinder having an enlarged diameter (20.64 mm {0.8126 in}), brake pedal operability has been improved.
For vehicles with DSC, the diameter of the pipe between the master cylinder and the DSC HU/CM has been increased, improving response during DSC operation.
Construction
Except for the cap and brake fluid reserve tank, the master cylinder cannot be disassembled. Therefore, if there is any malfunction in the interior of the master cylinder, replace the cylinder component without disassembling.

Operation
When the brake pedal is depressed, the push rod of the power brake unit presses in the master cylinder piston. By pressing in the piston, pressure is applied to the brake fluid to operate the brakes.
Low And Reverse Brake [Fw6 A EL, Fw6 Ax EL]
Master CylinderRain Sensor
Outline
The rain sensor detects the amount of rainfall and calculates the wiper operation
speed, and outputs a windshield wiper control signal to the front body control
module (FBCM) to perform automatic wiper operation (auto wiper system) according
to the amount of rainfall.
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Seat Weight Sensor Control Module Removal/Installation [Two Step Deployment
Control System]
CAUTION:
When the seat weight sensor control module is replaced with a new one, perform
the seat weight sensor calibration using the M?MDS..
1. Switch the ignition to off.
2. Disconnect the negative battery cable and wait for 1 min or more..
3. Disconnect the connectors.
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Recliner Motor Inspection
WARNING:
Handling a side air bag improperly can accidentally operate (deploy) the
air bag, which may seriously injure you. Read the service warnings/cautions
in the Workshop Manual before handling the front seat (side air bag integrated)..
1. Disconnect the negative battery cable ...