2008 MITSUBISHI LANCER EVOLUTION X Functions

CONSTRUCTION DESCRIPTION
FOUR-WHEEL ANTI-LOCK BRAKE SYSTEM (4ABS)35B-7
ABS-ECUM2351003000520
•By integrating ABS-ECU into the hydraulic unit,
no wiring harness for sending drive signal of the
solenoid valve and pump motor is required,
assuring higher reliability.
•Self-diagnostic and memory functions are inte-
grated into ABS-ECU. If any malfunction is
detected by the self-diagnostic function,
ABS-ECU activates a fail-safe function and illumi
-
nates the ABS warning light and brake warning
light
*.
NOTE: *: The brake warning light is used as the
EBD control warning light.
•ABS-ECU detects vehicle speed from the signals
of the wheel speed sensor and its recognizes the
wheel rotation status, estimates the wheel slip
condition based on the preprogrammed algo
-
rithm, and then controls the solenoid valve in the
hydraulic unit so that the wheels do not lock.
ABS hydraulic pressure control
ABS control cycle
1. The ABS-ECU calculates the speed and deceler-
ation of each wheel based on the signals from the
four wheel speed sensors, and estimates the
vehicle speed at that time.
2. When the brake pedal is depressed, the brake
fluid pressure applied to the wheel cylinder
increases, and the wheel speed decreases.
When the difference between the wheel speed
and vehicle speed increases, and the vehicle
deceleration goes below the specified value (Point A), ECU determines that the wheels are
about to be locked. At this time, ECU reduces the
brake fluid pressure by outputting the pressure
decrease signal to the solenoid valves (IN, OUT).
(between a and b)
3. When the vehicle deceleration and wheel speed
begin recovery, and the vehicle speed reaches
the point B, ECU outputs the pressure hold signal
to maintain the wheel cylinder fluid pressure.
(between b and c)
AC506830AB
a
b
cd A
BC
D
e Increase
Hold
Decrease
Wheel speed
Brake pressureActual vehicle speedEstimated vehicle speed

CONSTRUCTION DESCRIPTION
FOUR-WHEEL ANTI-LOCK BRAKE SYSTEM (4ABS)35B-8
4. When the wheel speed deceleration is further
recovered and overpasses the point C, ECU
determines that the wheel lock possibility has
been eliminated and increases the brake fluid
pressure by outputting the pressure increase sig
-
nal again. (between c and d)
5. Brake fluid pressure is controlled by repeating the
increase and hold of the pressure. (between d
and e)
6. When the wheel deceleration goes below the
threshold again, ABS-ECU controls the brake
fluid pressure by repeating the cycle (Step 2 to 5).
Four-wheel control
ABS fluid pressure is controlled independently for
four wheels.
EBD fluid pressure control
EBD control is activated in a range with lower slip
ratio where ABS is disabled. EBD calculates vehicle
deceleration and slip amount of the four wheels
based on the wheel speed sensor signal. If the rear
wheel speed differs from the vehicle speed by a cer
-
tain level or more, EBD increases, holds, and
decreases the pressure at the rear wheel control
solenoid valve in the hydraulic unit, and then adjusts
rear wheel brake fluid pressure fairly close to an
ideal distribution curve.
INITIAL CHECK
ABS-ECU performs the following initial checks using
the diagnostic functions. ABS-ECU illuminates the
ABS warning light for 3 seconds (including the initial
check)
* after the ignition switch is turned ON. If any
malfunction is detected, ABS-ECU continues illumi
-
nating the ABS warning light and disables ABS con-
trol.
NOTE: *: The ABS warning light may stay on after
the ignition switch is turned ON until the startup vehi
-
cle speed reaches approximately 10 km/h (6 mph).
As the ABS-ECU memorizes any diagnostic trouble
code related to the wheel speed sensor malfunction
recorded during the previous ignition ON status,
ABS-ECU continues illuminating the ABS warning
light until it verifies that the malfunction for that code
is resolved (startup check).
.
INITIAL CHECK
Performs self-diagnosis in ABS-ECU.
AC208548AB
Ideal distribution curve when
seated by fixed personsEBD operating conceptual design
Rear braking force
Ideal distribution curve when seated by one personsBraking force distribution curve
by the existing proportioning valveBraking force distribution
by EBD control
Front braking forceBraking Force
Improved

CONSTRUCTION DESCRIPTION
FOUR-WHEEL ANTI-LOCK BRAKE SYSTEM (4ABS)35B-11
NOTE: .
•*1 This diagnostic trouble code is not set within
the vehicle speed of 20 km/h (12 mph) or less.
•*2 Turns ON when two or more wheels are faulty.
•*3 Stays ON until the vehicle speed reaches 10
km/h (6 mph) when the ignition switch is turned to
ON next time.
DIAGNOSTIC FUNCTION
ABS-ECU has the following functions for easier sys-
tem checks. The following items can be diagnosed
using scan tool.
•Diagnostic trouble code set
•Service data output
•Actuator test.
DIAGNOSTIC TROUBLE CODE SET
There are 43 diagnosis items. Since all the diagnos-
tic results are recorded in volatile memory
(EEPROM*), they are stored in the memory even
though the battery terminals are disconnected.
NOTE: .
•*EEPROM (Electrical Erasable & Programmable
ROM): Special type of memory that can be pro
-
grammed or erased electrically
•For each diagnosis item, refer to Service Manual.
.
SERVICE DATA OUTPUT
Using scan tool, the input data sent from the sensors
and switches can be read.
NOTE: For service data items, refer to Service Man-
ual.
.
C2116Abnormality in pump motor
power supply voltageExecutedProhibitedExtinguishedIlluminated*3
C1000Abnormality in stop light switch
circuitExecutedExecutedExtinguishedExtinguished
C2200Abnormality in ABS-ECUProhibitedProhibitedIlluminatesIlluminates
C2100Battery
voltage
problem (low
voltage)9.7 ± 0.3 V or
less
*1
ExecutedProhibitedExtinguishedIlluminates
8.0 ± 0.5 V or
less
*1
ProhibitedProhibitedIlluminatesIlluminates
C2101Battery
voltage
problem (high
voltage)18.0 ± 1.0 V or
moreProhibitedProhibitedIlluminatesIlluminates
C1395Brake fluid filling not completedExecutedExecutedExtinguishedFlashes (1 Hz)
C2203VIN not writtenExecutedExecutedExtinguishedIlluminates
C1608Implausible diagnosis dataExecutedExecutedExtinguishedExtinguished
U0001Bus offExecutedExecutedExtinguishedExtinguished
U0100Engine time-out errorExecutedExecutedExtinguishedExtinguished
U0141ETACS time-out errorExecutedExecutedExtinguishedExtinguished
U1415Variant coding not implementedExecutedProhibitedExtinguishedIlluminates
U1417Invalid variant coding value
(including wrong assembly)ExecutedProhibitedExtinguishedIlluminates
DTC
No.Item Countermeasures for failure
EBD control ABS control Brake
warning lightABS warning
light

OIL PUMP
POWER STEERING37-6
Secondary collision
When the driver's body falls against the steering wheel via the
deployed air bag, the column bracket moves forward by
deforming the rivet pin of the one-way capsule, and simulta
-
neously the steering column assembly frees from the pin of col-
umn bracket to move forward and downwards.
OIL PUMPM2370004000373
The oil pump is a vane type with a fluid flow control
system which functions so the steering wheel turning
effort will be reduced at low engine speeds and
increase at higher speeds. The oil pump is essentially the same as the conven-
tional one in construction.
AC611053AB
AA
BB
One way
capsule
Section B - BSection A - A Column
bracketRivet pin
Column pipe Before collision
After collision
AC607645AB
A
AColumn
bracket
Column pipe
Pin Section A - A