2006 MITSUBISHI LANCER ECU

TROUBLESHOOTING
ENGINE COOLING14-6
INSPECTION PROCEDURE FOR
TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1: Cooling Fan (L.H.) and Cooling Fan (R.H.) <4G1 (Vehicles with A/C)> or
A/C Condenser Fan <4G6> do not Operate
Wire colour code
B : Black LG : Light green
G : Green L : Blue
W : White Y : Yellow
SB : Sky blue BR : Brown
O : Orange GR : Gray
R : Red P : Pink V : Violet
FAN CONTROL
RELAY
A-09XENGINE CONTROL
RELAY
B-16X
AC303577
A-18-1
COOLING FAN
MOTOR (L.H.)
COOLING FAN
MOTOR (R.H.)
<4G1 (VEHICLES
WITH A/C>
OR
A/C CONDENSER
FAN MOTOR <4G6> A-18-2
A-18
COOLING FAN
MOTOR DRIVE
CONTROL UNIT 1 A-13
12 C-111
ENGINE-ECU OR
ENGINE-A/T-ECU
21 C-123
18 C-122
615 121179
810234
(MU802322)
(MU801824)
C-123
(MU803784)C-122
(MU802611)A-13
C-111 L
L 2
22 11
1B
L
2
3
4
B-W
FUSIBLE
LINK No.2
B3
1
R-Y
R-Y
8 A-13
11 C-111
615 121179
810234
(MU802611)
J/C (6)
C-12
C-134
R-Y
3328
A-13
C-111
Cooling Fan (L.H.) and Cooling Fan (R.H.) or A/C Condenser Fan Drive Circut
AB
CIRCUIT OPERA T ION
•The cooling fan motor drive contro l unit is pow-
ered from fusible link (2).
•The engine-ECU o r engine-A/T - ECU
/T> use s in pu t sign als fro m th e A/C switch , t h e
water t
e mpe r ature sensor unit and the vehicle
speed sensor T > or the outpu t sha f t speed
senso
r to control the speed of the coo ling
fan
moto r (L.H.) and the cooling fa n mot o r (R.H.)
<4G1 (V
ehicles wit h A/C)> or A/C co ndenser fan
motor <4G6>.

TROUBLESHOOTING
ENGINE COOLING14-7
•The engine-ECU or engine-A/T-ECU
controls the cooling fan motor drive control
unit to activate the cooling fan motor (L.H.) and
the cooling fan motor (R.H.) <4G1 (Vehicles with
A/C)> or A/C condenser fan motor <4G6>.
TECHNICAL DESCRIPTION
•The cause could be a malfunction of the cooling
fan motor drive control unit power supply or earth
circuit.
•If the communication line wiring harness between
the cooling fan motor drive control unit and the
engine-ECU or engine-A/T-ECU is
short-circuited to earth, the cooling fan motor
(L.H.) and the cooling fan motor (R.H.) <4G1
(Vehicles with A/C)> or the A/C condenser fan
motor <4G6> will not rotate.
•The cause could also be a malfunction of the
cooling fan motor (L.H.).
•The cause could also be a malfunction of imput
signal from the A/C switch, the water temperature
sensor unit and the vehicle speed sensor
or the output shaft speed sensor to the
engine-ECU or engine-A/T-ECU .
•The cause could also be a malfunction of the
cooling fan motor drive control unit or the
engine-ECU or engine-A/T-ECU .
TROUBLESHOOTING HINTS
•Malfunction of fusible link (2)
•Malfunction of fan control relay
•Malfunction of cooling fan motor (L.H.) without A/C>
•Malfunction of cooling fan motor drive control unit
•Malfunction of engine-ECU or
engine-A/T-ECU
•Damaged wiring harness or connector
DIAGNOSIS
STEP 1. Check the cooling fan motor (L.H.).

Refer to P.14-24.
Q: Is the cooling fan motor (L.H.) in good condition?
YES : Go to Step 2 .
NO : Replace the cooling fan motor (L.H.) (Refer
to
P.14-33) <4G1> (Refer to P.14-35)
<4G6>. Then go to Step 24 .
STEP 2. Measure the power supply voltage at
cooling fan motor drive control unit connector
A-18.
AC100293
A-18
321
Connector: A-18
AD
(1)D isconn ect cooling f an motor drive contro l unit
conne ctor A-18 a nd measure wirin g har ness side
connector .
(2)T urn t he ig nition switch t o the "ON" positio n.
AC000246AF
A-18 Connector
(Component side)
(3)M easu r e the volt age between cooling fan motor
drive control unit con nect o r A-18 te rmin al 3 a nd
bod y ea rth.
•The voltage shou ld measu r e syste m volt age.
(4)T urn t he ig nition switch t o the "L OCK" (OF F )
position.
(5)C onne ct cooling fa n mot o r drive control unit
connector A-18.
Q:Is t h e mea s ure d volt a g e sy ste m v o lt ag e?
YES : Go to S t ep 1 7 .
NO : Go to S t ep 3 .

TROUBLESHOOTING
ENGINE COOLING14-13
STEP 18. Check the cooling fan motor drive
control unit connector A-18.
AC100293
A-18
321
Connector: A-18
AD
Q:Is t h e con n ec tor in goo d c ondit i o n ?
YES : Go to S t ep 19 .
NO : Repa ir or replace the conne ctor . Th en go to
S
t ep 24
.
STEP 1 9 . Check th e harness wire b e twee n
cooling fa
n motor drive control uni t connec tor
A-1
8 terminal 1 and b ody earth.
AC100293
A-18
321
Connector: A-18
AD
Q:Is t h e har n es s wire in good c ondition ?
YES : An intermittent malf unction is suspe c ted
(Refer to GROUP 00 - How to use
troub lesh ooting
P.00-5).
NO : Repa ir the dama ged harness wire. Then go
to S
t ep 2 4
.
STEP 2 0 . Check t he cooli ng fan m o tor drive
control unit
connecto r A-18 , intermed iate
connecto
r A-13 or C-1 1 1
H . dri ve ve hicles> and en gine-ECU conne ctor
C-1
23 or engin e -A/T -ECU connec tor C-122
T >.
AC100293
A-18
321
Connector: A-18
AD
AC303526
Connector: A-13
AB
A-13
A-13
AC303527
Connector: C-111
AB
C-111
C-111
615 121179
810234

AC303555AB
Connector: C-123 , C-122 C-123
or
C-122
C-123
Engine-ECU or
engine-A/T-ECU
C-122
TROUBLESH OOTING
ENGINE COOLING14-14
Q: Are t h es e con n ec tor s in go od con d ition?
YES : Go to S t ep 21 .
NO : Repa ir or replace the conne ctor . Th en go to
S
t ep 24
.
ST EP 2 1 . Check t he harness wire b e twe en
cooling f
an motor drive control uni t connec tor
A-1
8 te rm inal 2 an d en gine-ECU c onnec tor C-123
terminal 2
1 or engine -A/T -ECU con nector
C-1
22 termina l 18 .
AC100293
A-18
321
Connector: A-18
AD
AC303555AB
Connector: C-123 , C-122
C-123
or
C-122
C-123
Engine-ECU or
engine-A/T-ECU
C-122
Q: Are t h es e har n es s wires in go od cond it ion?
YES : Go to S t ep 2 2 .
NO : Repa ir the dama ged harness wire. Then go
to S
t ep 2 4
.

TROUBLESHOOTING
ENGINE COOLING14-15
STEP 22. Check the cooling fan motor drive
control unit.
AC303555AB
Connector: C-123 , C-122 C-123
or
C-122
C-123
Engine-ECU or
engine-A/T-ECU
C-122
(1) D isconn ect e ngin e -ECU conne ctor C-12 3
or e ngine -A/T -ECU conne ctor C-12 2 .
AC303559
C-122 connector
(Harness side connector: ECU side view)
AB
C-123 connector
(Harness side connector: ECU side view)
(2)P ull out conne ctor t e rminal p i n 21 or 18
to discon nect conn ector .
(3)R eco nnect t he con necto r with conn ector ter m in al
pin still removed.
(4)T urn t he ig nition switch to the "ON" positio n.
(5)C heck fo r the cooling fan opera t ion.
•The cooling fan ro t a t e s. (with conne ctor termi-
nal pi n 21 or 18 disconn ecte d)
•The cooling fan stop s. (When con necto r ter-
minal pi n 21 o r 1 8 is conn ected
to the
body earth.)
(6)T urn t he ig nition switch t o the "OFF" po sit i on.
(7)D isconn ect e ngin e -ECU conne ctor C-12 3
or e ngine -A/T -ECU conne ctor C-12 2 , a nd
push in con nect o r terminal pin 21 or 18
to discon nect conn ector .
(8)R econnect the con necto r with conn ector te rmin al
pin still inst alled.
Q:Doe s the cooling fa n rot a te ? And wh en th e
c onne ct or te rmin a l p i n is co nnec t e d to t h e bod y
e a rt h, d o es t h e co olin g f a n s t op ?
YES : Go to S t ep 2 3 .
NO : Replac e th e coo lin g fan motor d r ive con t rol
unit (Refer to
P.14-33) <4G1> (Refer to
P.14-35) <4G6>. Then go to S t e p 24 .
STEP 2 3 . M.U.T . -II/III self-dia g code
Check if an MPI system self- d iag code is set. (Ref er
to GROUP
13A - T r ouble shooting
P.13A-9) <4G1>
or (Refer to GROUP 13 B - T r ouble sho o ting
P.13B-9) <4G6>.
Q:Diagn o sis co de se t?
YES : Inspecti on chart fo r dia gnosis code (Re f er
to GROUP 13A - T r ou ble shoot ing
P.13A-15) <4G1 > or Inspection chart for
diagnosis code (Re f er to GROUP 13B -
T
r ouble sh ootin g
P.13B-15) <4G6>.
NO : Replac e th e engine-ECU or
engine-A/T
- ECU (Refer to GROUP
13A
P.13A- 384). Then go t o S t ep 24 .
STEP 2 4 . Check t he sym ptoms.
Q:Doe s the cooling fa n moto r ( L .H.) and t h e coo l ing
fa n mo to r ( R .H. ) <4G 1 (V ehicles with A/ C)> or A/C
c onde nse r fa n mo tor <4G6> o p era t e c o rre ct ly ?
YES : This symptoms is comple te.
NO : Return to S t ep 1 .

TROUBLESHOOTING
ENGINE COOLING14-16
INSPECTION PROCEDURE 2: Cooling Fan (L.H.) and Cooling Fan (R.H.) <4G1 (Vehicles with A/C)> or
A/C Condenser Fan <4G6> do not Change Speed or Stop
COOLING FAN (L.H.) AND COOLING FAN
(R.H.) OR A/C CONDENSER FAN DRIVE
CIRCUIT
Refer to P.14-6.
CIRCUIT OPERATION
Refer to P.14-6.
TECHNICAL DESCRIPTION
•If the communication line wiring harness between
the cooling fan motor drive control unit and the
engine-ECU or the engine-A/T-ECU
is open, the cooling fan motor (L.H.) and
the cooling fan motor (R.H.) <4G1 (Vehicles with
A/C)>, or the A/C condenser fan motor <4G6>
rotate to prevent the engine from overheating.
•If the system voltage is continuously supplied to
the cooling fan motor drive control unit by a fan
motor relay malfunction and a short circuit on the
cooling fan motor drive control unit power supply
wiring harness, the cooling fan motor (L.H.) and
the cooling fan motor (R.H.) <4G1 (Vehicles with
A/C)>, or the A/C condenser fan motor <4G6>
rotate.
•The cause could also be a malfunction of the
cooling fan motor (L.H.).
•The cause could also be a malfunction of input
signal from the A/C switch, the water temperature
sensor unit and the vehicle speed sensor
or the output shaft speed sensor to the
engine-ECU .
•The cause could also be a malfunction of the
cooling fan motor drive control unit or the
engine-ECU or engine-A/T-ECU .
TROUBLESHOOTING HINTS
•Malfunction of fan control relay
•Malfunction of cooling fan motor (L.H.) without A/C>
•Malfunction of cooling fan motor drive control unit
•Malfunction of engine-ECU or
engine-A/T-ECU
•Damaged wiring harness or connector
DIAGNOSIS
STEP 1. Check the fan control relay.
Refer to P.14-23.
Q: Is the fan control relay in good condition?
YES : Go to Step 2 .
NO : Replace the fan control relay. Then go to
Step 8
.
STEP 2. Check the fan control relay connector
A-09X.
AC303510AB
Fan control relay
Relay boxConnector: A-09X
A-09X
Q:Is t h e con n ec tor in goo d c ond it io n?
YES : Go to S t ep 3 .
NO : Repa ir th e con nect o r or rep l ace the re lay
box. Then
go to S t ep 8
.
STEP 3 . Check the harness wire be twee n fan
control relay
connec tor A-0 9 X terminal 2 and
cooling f
an motor drive control uni t connec tor
A-1
8 terminal 3.
AC303510AB
Fan control relay
Relay boxConnector: A-09X
A-09X

AC100293
A-18
321
Connector: A-18
AD
TROUBLESHOOTING
ENGINE COOLING14-17
Q: Is t h e har n es s wire in good c ondition ?
YES : Go to S t ep 4 .
NO : Repa ir the dama ged harness wire. Then go
to S
t ep 8
.
STEP 4. Ch eck the cooling fan moto r d r iv e
control unit c
onnecto r A-18 , intermed iate
connecto
r A-13 or C-1 1 1
dri ve veh icles> and en gine-ECU connec tor
C-1
23 or engin e -A/T -ECU connec tor C-122
.
AC100293
A-18
321
Connector: A-18
AD
AC303526
Connector: A-13
AB
A-13
A-13
AC303527
Connector: C-111
AB
C-111
C-111
615121179
810234
AC303555AB
Connector: C-123 , C-122
C-123
or
C-122
C-123
Engine-ECU or
engine-A/T-ECU
C-122
Q: Are t h es e con n ec tor s in g ood con d ition?
YES : Go to S t ep 5 .
NO : Repa ir or replace the conne ctor . Th en go to
S
t ep 8
.

TROUBLESHOOTING
ENGINE COOLING14-18
STEP 5. Check the harness wire between cooling
fan motor drive control unit connector A-18
terminal 2 and engine-ECU connector C-123
terminal 21 or engine-A/T-ECU connector
C-122 terminal 18 .
AC100293
A-18
321
Connector: A-18
AD
AC303555AB
Connector: C-123 , C-122 C-123
or
C-122
C-123
Engine-ECU or
engine-A/T-ECU
C-122
Q: Are t h es e har n es s wires in goo d cond it ion?
YES : Go to S t ep 6 .
NO : Repa ir the dama ged harness wire. Then go
to S
t ep 8
.
STEP 6 . Check the cooling fan moto r d r iv e
control unit.
AC303555AB
Connector: C-123 , C-122
C-123
or
C-122
C-123
Engine-ECU or
engine-A/T-ECU
C-122
(1) D isconn ect e ngin e -ECU conne ctor C-12 3
or e ngine -A/T -ECU conne ctor C-12 2 .
AC303559
C-122 connector
(Harness side connector: ECU side view)
AB
C-123 connector
(Harness side connector: ECU side view)
(2)P ull out conne ctor terminal p i n 21 or 18
to discon nect conn ector .
(3)R econnect the con necto r with conn ector te rmin al
pin still removed.
(4)T urn t he ig nition switch t o the "ON" positio n.
(5)C heck fo r the cooling fan opera t ion.
•The cooling fan ro t a t e s. (with conne ctor termi-
nal pi n 21 or 18 disconn ecte d)
•The cooling fan stop s. (When con necto r ter-
minal pi n 21 o r 1 8 is conn ected
to the
body earth.)
(6)T urn t he ig nition switch t o the "OFF" po sit i on.
(7)D isconn ect e ngin e -ECU conne ctor C-12 3
or e ngine -A/T -ECU conne ctor C-12 2 , a nd
push in con nect o r terminal pin 21 or 18
to discon nect conn ector .