brake MITSUBISHI LANCER EVOLUTION X 2008 User Guide

CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-6
VARIABLE BOOST RATIO MECHANISM
The variable boost ratio mechanism changes the input/output
characteristics of the brake booster in two phases by changing
the reaction force applied to the valve plunger during the assist
phase.
.
AT INITIAL ASSISTING
1. When the brake pedal is not depressed (no input load
applied), the reaction washer is not deformed.
2. When the brake pedal is depressed, the reaction washer is
deformed to reach the ring piston and disc, then the first
input characteristics begin (Ratio 1).
.
AT AN INCREMENT OF ASSIST RATIO
1. The reaction washer is further deformed and pushes down
the ring piston and lock washer, deflecting the spring. All the
force pushing the ring piston and disc is transferred to the
brake pedal via spring seat and disc as the reaction force.
2. The reaction washer is then further deformed, and when the
lock washer makes contact with the control housing, the
input characteristics change. All the force applied from the
reaction washer to the ring piston is now transferred to the
control housing via the lock washer, so no force is applied to
the brake pedal. The second input characteristics (Ratio 2)
begin.
AC507766AB
Disc
Reaction
washer
Ring piston
AC507768AB
Valve
piston Spring
seat Spring
Lock washer
AC507769AB
Reaction
washer
Ring piston
Control
housing
Lock washer

CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-7
BRAKE PEDALM2350007000422
The brake pedal retreat suppression mechanism that
restraints the retraction of the brake pedal surface
during a frontal collision has been adopted in order to
reduce the shock to the driver's feet.When the brake booster is crushed rearward by the
engine retreat during a frontal collision, the installa
-
tion surface of the brake pedal is retreated. In this
case, the end of the pedal support is forcibly slid
down and back by the interference with the slope
mounted on the front deck crossmember assembly.
At the same time, the linkage comprised of the pedal
support, pedal arm, and push rod moves the brake
pedal pad surface forward.
AC611958AB
Pedal support frame
position before collision
Collision loadPedal retreat
path in collision
Brake booster
Brake pedal and support
memberSlopeBrake pedal and support
member
Slope
After the breakage
mechanism operates
Pedal support frame position after
collision Brake booster
Pedal arm
Push
rodPush
rod
Pedal arm

CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-8
FRONT BRAKEM2350003000602
Brakes with the following specifications have been
adopted for the front brakes.
•The 1-piston ventilate disc brake (V5-S57 cles with 16-inch wheel> or V6-S57 with 18-inch wheel>) has been adopted.
•An audible wear indicator that informs the driver
of application limit has been adopted onto the
front brake LH pads.
•The outer disc type brake disc which can be tight-
ened together with the wheel has been intro-
duced for better serviceability.
.
DISC BRAKE DESIGNATION
AC609316
AC201769
Wear indicator Brake discPad Normal
AB
At wear limit
<15-inch disc brake (V5-S57)>
<16-inch disc brake (V6-S57)>
No.ItemContents
1Brake disc typeV: Ventilated
S: Solid
2Brake size
(Minimum applicable
disc wheel)
4: 14"
5: 15"
6: 16"
3Number of pistonsS: 1 (Floating type)
4Piston size
(Rounded integral
value)
35: φ 34.9 mm
57: φ 57.1 mm
V 6 - S 57
1 2 3 4
AC505124

CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-9
REAR BRAKEM2350004000616

8-inch leading trailing-type drum brakes have been
adopted for the rear brakes in order to provide stable
braking force at all times both when moving forward
and reverse.

Brakes with the following specifications have been
adopted for the rear.
•The 1-piston solid disc brake (S4-S35 with 16-inch wheel> or S6-S35 18-inch wheel>) has been adopted.
*
•An audible wear indicator that informs the driver
of application limit has been adopted onto the
brake pads.
•The outer disc type brake disc which can be tight-
ened together with the wheel has been intro-
duced for better serviceability.
NOTE: *For the brake disc name, refer to FRONT
BRAKE
P.35A-8.
AC609282
AC609315
AC201769
Wear indicator Brake discPad Normal
AB
At wear limit
<16-inch disc brake (S6-S35)> <14-inch disc brake (S4-S35)>

CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-10
BRAKE LINEM2350005000266
PROPORTIONING VALVE
A proportioning valve is used to prevent early locking
of the rear wheels, in order to provide improved sta
-
bility during braking.
AC609305
From master cylinder rear brake system
To rear brakeO-ring U-packing Sleeve
Guide Seal
Proportioning valveMaster cylinder
SpringPlateValve
AB

35B-1
GROUP 35B
FOUR-WHEEL
ANTI-LOCK BRAKE
SYSTEM (4ABS)
CONTENTS
GENERAL INFORMATION . . . . . . . .35B-2
CONSTRUCTION DESCRIPTION . . .35B-6
SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . 35B-6
ACTUATORS . . . . . . . . . . . . . . . . . . . . . . . 35B-6
ABS-ECU. . . . . . . . . . . . . . . . . . . . . . . . . . . 35B-7

GENERAL INFORMATION
FOUR-WHEEL ANTI-LOCK BRAKE SYSTEM (4ABS)35B-2
GENERAL INFORMATIONM2351000100830
The ABS that ensures directional stability and con-
trollability during hard braking. ABS is standard
equippment on the ES and GTS models but is
optional.
This ABS uses a 4-sensor system that controls all
four wheels independently of each other, and has the
following features:
•EBD *1 (Electronic Brake-force Distribution sys-
tem) control that can obtain ideal rear wheel
brake force has been employed.
•The magnetic encoder for detecting the wheel
speed has been installed instead of the rotor as
the wheel speed sensor.
•For wiring harness saving and secure data com-
munication, CAN *2 bus has been adopted as a
tool of communication with other ECUs.
NOTE: .
•*1: EBD (Electronic Brake-force Distribution)
•*2: For more information about CAN (Controller
Area Network), refer to GROUP 54C
P.54C-2.
.
SPECIFICATIONS
.
CONSTRUCTION DIAGRAM
.
ItemSpecifications
ABS control type4 sensors
Wheel speed sensorMagnetic encoderFront86 (N pole: 43, S pole: 43)
Rear86 (N pole: 43, S pole: 43)
Ty p eSemiconductor
AC608518
CHECK
SERVICE
REQUIRED
AB
56
6
5
11
22 3
7 4, 8
12

GENERAL INFORMATION
FOUR-WHEEL ANTI-LOCK BRAKE SYSTEM (4ABS)35B-3
MAIN COMPONENTS AND FUNCTIONS
.
Parts nameNo.Functional description
SensorWheel speed sensor1Outputs the frequency signal in proportion to the
rotation speed of each wheel to ABS-ECU.
Magnetic encoder for
wheel speed detection2The wheel speed sensor is a pulse generator. When
the magnetic encoder for wheel speed detection (a
plate on which north and south pole sides of the
magnets are arranged alternately) rotates, it outputs
frequency pulse signal in proportion to each wheel
speed.
Stop light switch3Outputs the signal indicating whether the brake pedal
is depressed or not through ETACS-ECU to ABS-ECU
via the CAN line.
ActuatorHydraulic unit4Drives the solenoid valve using the signal from
ABS-ECU, and controls the brake fluid pressure for
each wheel.
ABS warning light5Informs the driver of the system status by illuminating,
flashing, or turning off the warning light according to
the signal from ABS-ECU.
Brake warning light6Used as the warning light for the parking brake, brake
fluid level, and EBD control. Informs the driver of the
system status by illuminating or turning off the warning
light according to the signal from ABS-ECU, ETACS or
combination meter.
Data link connector7Establishes the communication with scan tool.
ABS control unit (ABS-ECU)8Controls the actuators (described above) based on the
signals coming from each sensors.
Controls the self-diagnostic functions and fail-safe
functions.
Controls diagnostic function (Compatible with scan
tool).

GENERAL INFORMATION
FOUR-WHEEL ANTI-LOCK BRAKE SYSTEM (4ABS)35B-4
SYSTEM CONFIGURATION
NOTE: Dashed lines indicate the CAN bus communi-
cation lines.
.
AC608528AB
Wheel speed sensor (FL)
ECU power supplyABS-ECU
Combination meter
(Brake warning lamp,
ABS warning lamp)
Data link connector Wheel speed sensor (RL)
Wheel speed sensor (RR)
Wheel speed sensor (FR)
Stop light switch Front-right wheel (FR)
Hydraulic unit Stop light switch
ETACS-ECU
Wheel
speed
sensor
(FL) Wheel
speed
sensor
(FR)Wheel
speed
sensor
(RR)
Wheel
speed
sensor
(RL) Control solenoid valve (RL) OUT Control solenoid valve (RR) OUT Control solenoid valve (FL) OUT Control solenoid valve (FR) OUT Control solenoid valve (FR) IN
Control solenoid valve (FL) IN
Control solenoid valve (RR) IN
Control solenoid valve (RL) IN
Rear right wheel (RR)
Rear left wheel (RL) Front left wheel (FL)

GENERAL INFORMATION
FOUR-WHEEL ANTI-LOCK BRAKE SYSTEM (4ABS)35B-5
ABS ELECTRICAL DIAGRAM
AC609237
Ignition
switch (IG1) Fusible
link No.34Fusible
link No.36 Fusible
link No.27Fusible
link No.26
Analog
interface
circuitAnalog
interface
circuit CAN drive circuit
Interface circuit
Solenoid valve Stoplight
switch
Motor Hydraulic unitStoplightEngine
control
module Data link
connector
Solenoid valve
power supplySolenoid valve
power supply
Motor power supplyMotor power supplyPower supplyCAN drive
circuit
Interface
circuit
CAN transceiver
circuit
CPU
LED drive
circuitInterface
circuit
Interface circuit
Wheel speed sensor (FL) (FR) (RL) (RR)Relay box
(Engine
compartment)
Combination
meter
AB
ABS-ECUCAN drive
circuit
Interface
circuit ETACS-ECU