engine MITSUBISHI COLT 2006 Service Repair Manual

ELECTRICAL POWER STEERING
POWER STEERING37-10
ELECTRIC POWER STEERING-ECU
M2370000800106
AC207827AB
Glove box
Electric power
steering-ECU
The electric powe r stee ring-ECU is att a ch ed below
the glove
box, wh ich is integ r ated wit h an input inter
-
face circu i t, a microco m p u ter , an outp u t d r ive circuit,
a fail-sa
f e rela y , and a mot o r line relay et c.
It is also integrated with a self-diag nostic fu nction,
and illuminate
s the warn ing lamp an d set s d i agno sis
code
to the diagn osis connector .
CAN COMMUNICATION
The electric powe r stee ring-ECU perfo rms the da t a
transf
e r with a nother ECUs through CAN communi
-
cation.
SignalReceiver ECU
Engine-CVT-ECU or
engine-ECUMeter and A/C-ECU
Motor current signal•−
Electric power steering warning lamp request signal−•
NOTE: • ind i ca tes items which sends and re ceives
dat
a throu gh CAN communicat i on.
FA IL - SAFE FUNCTION
If the e l ectric power st eering - ECU de tect s any mal-
functi on, it illuminat es th e warnin g lamp, de activate s
the electric po
we r stee ring f unct i on, a nd the n
switches
the steerin g system in to ma nual mode .
DIAGNOSTIC FUNCTION
Electric po wer ste e ring -ECU has the following fu nc-
tions for easie r system ch ecks.
•Diagnosis code set
•Service dat a outp u t
All the above ite m s can be diagnosed using
M.U.T
. -III.
DIAGNOSIS CODE SET
There a r e 22 d i agno stic ite m s. Since all the d i agn os-
tic result s are recorded in volatile memory (EEP-
ROM*), they a r e sto r ed in the memo ry even th ough
the bat
tery t e rminals are d i sconne cted.
NOTE: .
•*: EEPROM (E lectrical Erasable & Programma-
ble ROM) Special ty pe o f me mory that can b e
prog
rammed or erase d ele c trically .
•For each diag nostic item, refer to the Mainte-
nance Manua l.
SERV ICE DA T A OUTPUT
Usin g M. U. T . -II I , t h e i n p u t d a t a s e n t f r om t h e se ns ors
and motors can
be rea d .
NOTE: For e a ch service dat a it em, re fer to th e Ma in-
tenance Manual.

ELECTRICAL POWER STEERING
POWER STEERING37-11
OPERATION
M2370000700110
IGNITION SWITCH ON
Ignition supply voltage is applied to the electric
power steering-ECU, and the ECU enters standby
mode.
IGNITION SWITCH ON
AC601668AC207635 AB
Electric power
steering-ECU
OFF
OFF MotorMotor current signal
Maximum limit value (50A)
Engine speed
Engine speed
ON
500 r/min or 15 km/h
max 0.5s 0.7s
Motor output Determination of motor
control start Temporary increase of motor
assist limit value
Engine-CVT-ECU or
engine-ECU
1.
Whe n th e e ngine is st arted, the en gine sp eed sig-
nal sent from the en gine -CVT -ECU or
eng
ine-ECU is inp u t to th e ele c tric power steer
-
ing-ECU.
2. Af ter st a r ting the engine, the electric power ste e r-
ing-ECU judges the engin e st atu s "ENGINE
SPEED ON"
when the engine speed reaches 500
r/min or
the vehicle speed reaches 1 5 km/h or
more, the
n the p o wer assist functio n is ready .
STEERING WHEEL OPERAT ION
AC400096
AC206443AB
Electric power
steering-ECU
Torque
sensor
Torque sensor
Motor Motor
Motor current
Torque sensor signal (main)
Torque sensor signal (sub)
F A IL- S AFE FUNCTION OPERA T ION
Duri ng t h e f a il -s af e m o d e , t h e el ect r ic powe r st ee rin g
operate
s as a manual ste e ring system.

COMMUNICATION METHOD
SMART WIRING SYSTEM (SWS)54B-3
COMMUNICATION METHOD
M2541001000527
AC206910
Engine-ECU or
Engine-CVT-ECU EPS-ECU
ABS-ECU*
1 or
ASC-ECU*2
ETACS-ECU
Combination meter
(incorporating meter-A/C-ECU)
AC
SWS
communication
Column switch
CAN
communication
: Bidirectional communication : Unidirectional communication
NOTE: 4A91
: 4G15
The following th ree type s of co mmunicatio n systems
are co
nnected as sh own for mutual commu n ication .
•SWS communicatio n system in wh ich a ded i-
cated signa l line for send ing mult iple x da t a con-
nects ET ACS-ECU and the column swit ch (in the
co
lum n ECU)
•CAN communication system in which twisted-p a ir
cables with h
i gh resist ance to noise conn ect
ET
ACS-ECU, engine-ECU ,
engine-CVT
- ECU , ABS -E CU <4A9>,
ASC-ECU <4G1>, EPS-ECU,
and the combina
-
tion meter (in the meter-A/C-ECU)
NOTE: For informatio n on CAN, refe r to GROUP
54C
P.54C-2.

MULTI-DISTRIBUTION INPUT/OUTPUT BY CIRCUIT
SMART WIRING SYSTEM (SWS)54B-6
Rear wiper washer
•Rear wiper•
AC207065
ETACS-ECU
AB
Circuit and Input Switch
ECUs and Switches
Connected by
Multi-Distribution
Output
• Ignition switch (IG1)
• Ignition switch (ACC)
Engine-CVT-ECU
• Inhibitor switch
Combination meter
•
Ignition switch (IG1) Column switch
(Rear wiper and
washer switch)
• Rear wiper motor
• Rear washer motor
: SWS communication line
: CAN communication line
Rear washer
Lighting
•Headlamp , t a il lamp•
AC401132AC
• Ignition switch (IG1)
• Fog lamp switch
• Driver's door switch
Combination meter
• High beam indicator lamp
• Fog lamp indicator lamp
•
Illumination lamps
• Headlamp
• Tail lamps
• Fog lamps
Combination meter
• Ignition switch (IG1) ETACS-ECU
Circuit and Input SwitchECUs and Switches
Connected by
Multi-Distribution
Output
Column switch
(Lighting switch)
: SWS communication line
: CAN communication line
Fog lamp

DIAGNOSTIC FUNCTION
SMART WIRING SYSTEM (SWS)54B-8
DIAGNOSTIC FUNCTION
M2541003000642
DIAGNOSIS CODE SET
For more information about diagnosis code output,
refer to the Workshop Manual.
SWS INPUT SIGNAL CHECK USING
M.U.T.-III
When the M.U.T.-III is connected to the diagnosis
connector and any of the SWS-linked switches is
operated, the PC buzzer sounds to evaluate whether
the switch is normal or not.
SWS INPUT SIGNAL CHECK AND ECU
CHECK BY USING SWS MONITOR
The switch signals sent by ECUs and the operations
of these ECUs can be confirmed by using the SWS
monitor and the M.U.T.-III.
INPUT SIGNALS THAT CAN BE CHECKED
Input signalCondition for sounding buzzerDisplay on
M.U.T.-III (when
SWS monitor is
used)
Ignition switch (ACC)Turn from "LOCK" (OFF) to "ACC" positionfrom OFF to ON
Ignition switch (IG1)Turn from "ACC" to "ON" positionfrom OFF to ON
Key reminder switchRemove the ignition key from ignition key cylinder
(form inserted position)from OFF to ON
Hazard lamp switchTurn from OFF to ONfrom OFF to ON
Fog lamp switch
Remote controlled mirror
switch (unfolding/folding
switch)
Speed signal When the speed changes from less than 10 km/h to
more than 10 km/hDisplays the
vehicle speed
Cranking signalWhile the ignition switch is in START position (while
cranking the engine)−
Selector lever P position signal
(parking)When the selector lever is shifted to the "P" position
(Ignition switch: ON or START)−
Selector lever R position signal
(reverse)When the selector lever is shifted to the "R" position
(Ignition switch: ON or START)−
Buzzer triggered by
ETACS-ECU
*1
When the following conditions are satisfied
•Ignition switch: LOCK (OFF) position
•Lighting switch: ON
•Driver’s door switch: ON (Driver’s door: OPEN)
ON
When requirements for sounding each warning buzzer
are not satisfiedOFF
Door switchDriver’s doorWhen door(s) or tailgate is opened from the closed
positionfrom OFF to ON
Passenger’s
door
Rear door
All door switchA door is opened when all the doors are closedfrom OFF to ON

SYSTEM OPERATION
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)52B-8
SYSTEM OPERATION
FRONT AIR BAG AND SEAT BELT WITH
PRE-TENSIONER
M2521000700059
AC313906
Frontal collision against
another vehicleor
Frontal collision against a
solid surface Analogue G-sensor
Ignition judgment
Shock
above a
certain
level
Ignition signal
SRS-ECU
Front air bag safing
G-sensor
Front impact
sensor (RH)
Front impact
sensor (LH)
AB
In case of a
front a l collision, if the front imp a ct sensor
in the
engine comp artment, th e ana logue G-sensor
in the
SRS-ECU and t he fron t air b ag sa fing sensor
simult
ane ously de tect an imp a ct th at excee d a cer
-
ta in threshold (turn ON), the SRS-ECU sen d s an
ignition
sign al to the air bag modu les (squ ibs) and
seat
belt p r e-tension e rs (squib s ) on the driver and
p
a sse nger sid e s, thus inflating the air bags an d op er
-
ating the seat be lt pre - tensioners.

GENERAL
ACTIVE STABILITY CONTROL SYSTEM (ASC)35C-2
GENERAL
M2357000200040
The active stability control system (ASC) has been
installed to the M/T vehicle.
•The active stability control system (ASC) has the
stability control and the traction control (TCL)
functions. By the integrated control with the
anti-lock brake system, the system stabilises the
vehicle attitude and at the same time secures the
driving force.
•When the stability control function determines
that the vehicle is in a dangerous condition, it
reduces the engine output and applies brake
force to four wheels independently to control the
vehicle behaviour, avoiding the critical state.
•The traction control (TCL) function prevents the
driving wheel slip on a slippery road surface,
ensuring easy startup, and at the same time,
secures proper driving force and improves steer
-
ing performance during cornering acceleration.
•Fail-safe function assures the security.
•Serviceability improvement
•For wiring harness saving and secure data com-
munication, the CAN* communication has been
adopted as a tool of communication with another
ECU.
NOTE: .
•*For more information about CAN (Controller
Area Network), refer to GROUP 54C
P.54C-2.
•ABS and ASC are controlled by ASC-ECU.
CONSTRUCTION DIAGRAM
AC600849AB
1 12
2
3
46
5
7
8
9, 10, 17
14
12
11
13
15
16

ComponentNo.Function
SensorWheel speed sensor1Sends alternating current signals at frequencies which are
proportional to the rotation speeds of each wheel to the
active stability control system-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 lamp switch3Sends a signal to the active stability control system-ECU
to indicate whether the brake pedal is depressed or not.
Parking brake switch4Outputs the signal indicating whether the parking brake
lever is pulled or not to ASC-ECU.
Brake fluid level switch5Outputs the signal indicating whether the brake fluid is
filled to the lowest limit level or not to ASC-ECU.
G and yaw rate sensor6Detects the lateral acceleration and the yaw rate for the
vehicle. Then it sends a signal through the CAN bus line to
the active stability control system-ECU.
Steering wheel sensor7Detects the steering wheel angle, and sends a signal to
the active stability control system-ECU through the CAN
bus line.
ASC OFF switch8Outputs the ASC ON/OFF signal to ASC-ECU.
Pressure sensor9Is incorporated in the hydraulic unit, and informs the active
stability control system-ECU of the brake fluid pressure in
the master cylinder.
ActuatorHydraulic unit10Drives the solenoid valves and pump motor according to
signals from the ABS/active stability control system-ECU in
order to control the brake hydraulic pressure for each wheel.
ABS warning lamp11Illuminates in response to signals from the active stability
control system-ECU when a problem develops in the
system.
Brake warning lamp12Illuminates in response to signals from the active stability
control system-ECU when a problem develops in the EBD
system or the brake fluid level is low.
Active stability control system
(ASC) indicator lamp 13Receives a signal from the active stability control
system-ECU, and flashes to inform the driver that the
system is operating, or illuminates to inform the driver of
system shutdown.
ASC OFF indicator lamp14Informs the driver of the ASC shutdown by illuminating
with the signal from ASC-ECU.
Diagnosis connector15Sets the diagnosis codes and allows communication with
the M.U.T.-III.
Engine-ECU16Receives a signal from the active stability control
system-ECU to control the engine output.
Anti-skid Brake/Active Stability Control
System control unit (ABS/active stability
control system-ECU)17Controls actuators (described above) based on the signals
coming from each sensor.
Controls the self-diagnostics and fail-safe functions.
Controls the diagnostic function (M.U.T.-III compatible).
GENERAL
ACTIVE STABILITY CONTROL SYSTEM (ASC)35C-3

GENERAL
ACTIVE STABILITY CONTROL SYSTEM (ASC)35C-4
SCHEMATIC DIAGRAM
AC600637AC
Combination meter
ABS warning lamp 
· Brake warning lamp
· Active stability control indicator lamp
· Active stability control OFF indicator lamp
Diagnosis
Connector
Control solenoid valve (FR) OUT
Control solenoid valve (FR) IN
Control solenoid valve (FL) OUT
Control solenoid valve (FL) IN
Control solenoid valve (RR) OUT
Control solenoid valve (RR) IN
Control solenoid valve (RL) OUT
Control solenoid valve (RL) IN Suction valve (FR)
Suction valve (FL)
Cut valve (FR)
Cut valve (FL) Pump motor
Active stability
control system-ECU
Front-left wheel speed sensor
Rear-left wheel speed sensor
Front-right wheel speed sensor Rear-right wheel speed sensor
Master cylinder pressure sensor Stop lamp switch
Parking brake switch
Brake fluid level switch
Power supply to active stability
control system-ECU Steering wheel sensor
G and yaw rate sensor
Engine-ECU
Steering wheel sensor
Front-right wheel (FR)
Wheel
speed
sensor
Engine-ECU
G and yaw rate sensor
Parking
brake
switch Rear-right wheel (RR)
Wheel
speed
sensor
Stop lamp switch
Hydraulic
unit Wheel speed
sensor Rear-left
wheel (RL)
Wheel speed
sensor
Front-left wheel (FL)
Note
: CAN-bus line

CONSTRUCTION DIAGRAM
ACTIVE STABILITY CONTROL SYSTEM (ASC)35C-8
EXAMPLE OF THE EFFECT OF CONTROL
AC204504
AC204505
AC204506AC204507AB
Restraining under-steering Restraining over-steering
Avoiding under-steering Avoiding wheel spin
Improving ABS performance
Stable vehicle attitude
after avoiding obstacles
Example of TCL control
When th e driving wheel slip s (ex. during drivin g on
low
µ road), TCL send s the engine out put red u ction
sign
al to the en gine ECU in order to prevent th e driv
-
ing f o r c e loss cau s e d by t he dr iving whe e l slip . A t t h e
same time, TCL a
pplies th e brake to t he slipp i ng
driving whe
e l so that the drivin g force is applied to
t
he non-slipping driving wheel, which co ntrols the slip
o
f th e drivi ng wheel, securin g the prop er d r iving f o rce
and increa
sed steering fo rce.
Fail-safe and diagnostic functions
ASC-ECU constantly mo nitors the input and ou tput
sign
als. If an error is det ected in th e syste m ,
ASC-ECU send
s a f a il sign al a nd the correspond ing
indicato
r lamp is illuminate d or blinks. V a riou s con
-
trols are proc essed depen ding on the cause of mal-
functi on a s shown below . ASC-ECU has the
follo
wing fu nctions for easier system checks.
•Diagnosis code set
•Service dat a outp u t
•Actuator te st
All the above it ems can be diagnosed using
M.U.T
. -III.