2006 MITSUBISHI LANCER ISC

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 COOLING14-8
STEP 3. 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 4 .
NO : Repa ir or replace the conne ctor . Th en go to
S
t ep 24
.
STEP 4 . Ch eck the fusible link No.2.
AC303509AB
Fusible link
No.2
Relay box
Q:Is t h e fu sible link No.2 in good c ondition ?
YES : Go to S t ep 5 .
NO : Replac e th e fusible lin k No.2. Then g o to
S
t ep 24
.
STEP 5. Measure the po wer suppl y volt age at fan
control relay
connect or A-09 X.
AC303510AB
Fan control relay
Relay boxConnector: A-09X
A-09X
(1)D isconn ect f an co ntrol relay co nnector A-09X (remove the fan control relay) and measure re lay
box side connector .
(2)
T urn t he ig nition switch t o the "ON" positio n.
AC303511AB
A-09X Connector
(Relay box side)
(3)M easu r e the volt age between fan control rela y
connector A-09X te rmin al 4 and bo dy e a 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 fa n con t rol re lay con necto r A-09X
(inst a ll the fan control relay).
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 8 .
NO : Go to S t ep 6 .
STEP 6 . Check the fan con trol re lay co nnector
A-0
9 X.
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 7 .
NO : Repa ir th e con nect o r or rep l ace the re lay
box. Then
go to S t ep 24
.

TROUBLESHOOTING
ENGINE COOLING14-10
STEP 11. Measure the terminal voltage at fan
control relay connector A-09X.
AC303510AB
Fan control relay
Relay boxConnector: A-09X
A-09X
(1)D isconn ect f an co ntrol relay co nnector A-09X
(remove the fan control relay) and measure re lay
box side connector .
(2)T urn t he ig nition switch to the "ON" positio n.
AC303517AB
A-09X Connector
(Relay box side)
(3)M easu r e the volt age between fan control rela y
co nnector A-09X te rmin al 1 and bo dy ea rth.
•The voltage should measu r e syste m volt age.
(4)T urn t he ig nition switch to the "L OCK" (OFF )
position.
(5) C onne ct fa n con t rol re lay conn ecto r A-09X
(inst a ll the fan control relay).
Q:Is t h e mea s ure d volt ag e sy ste m v o lt ag e?
YES : Go to S t ep 14 .
NO : Go to S t ep 12 .
STEP 1 2 . Check t he J/C No.6 C-12 vehicle
s > or C-134 ,
intermedia
t e conne ctor A-13 vehicle
s > C-1 1 1 a nd fan
control relay
connec tor A-0 9 X.
AC303524
Connector: C-12
AB
C-12
C-12
AC303525
Connector: C-134
AB
C-134
C-134
AC303526
Connector: A-13
AB
A-13
A-13
AC303527
Connector: C-111
AB
C-111
C-111
615121179
810234

AC303510AB
Fan control relay
Relay boxConnector: A-09X
A-09X
TROUBLESHOOTING
ENGINE COOLING14-11
Q: Are t h er e conn ect ors in go od cond it ion?
YES : Go to S t ep 13 .
NO : Repa ir or replace the conne ctor . Th en go to
S
t ep 24
.
STEP 1 3 . Check th e harness wire b e twee n J/C
No.
6 C-12 termina l 33 o r
C-1
34 termina l 33 and fan
control relay
connect or A-09 X terminal 1 .
AC303524
Connector: C-12
AB
C-12
C-12
AC303525
Connector: C-134
AB
C-134
C-134
AC303510AB
Fan control relay
Relay boxConnector: A-09X
A-09X
Q:Are t h es e har n es s wires in go od cond it ion?
YES : An intermittent malf unction is suspe c ted
(Refer to GROUP 00 - How to use
troub leshooting
P.00-5).
NO : Repa ir the dama ged harness wire. Then go
to S
t ep 2 4
.
STEP 1 4 . Check t he contin uity between fan
control relay
connec tor A-0 9 X and bod y earth.
AC303510AB
Fan control relay
Relay boxConnector: A-09X
A-09X
(1)D isconn ect f an control relay co nnector A-09X
(remove the fan control relay) and measure re lay
box side connector .
AC303533AB
A-09X Connector
(Relay box side)
(2) M ea sure th e resi st anc e b e t w e e n f an con t rol re lay
connector A-09X te rmin al 3 and bo dy e a rth.
•Continu i ty exist s .
(3)C onne ct fa n con t rol re lay con necto r A-09X
(inst a ll the fan control relay).
Q:Doe s the cont inuity e x ist s ?
YES : An intermittent malf unction is suspe c ted
(Refer to GROUP 00 - How to use
troub leshooting
P.00-5).
NO : Go to S t ep 15 .

TROUBLESHOOTING
ENGINE COOLING14-12
STEP 15. 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 ondit i o n ?
YES : Go to S t ep 16 .
NO : Repa ir the con nect o r or rep l ace the re lay
box. Then
go to S t ep 24
.
STEP 16 . Check th e harness wire b e twee n fan
control relay
connect or A-09 X terminal 3 and
body ea
rth.
AC303510AB
Fan control relay
Relay boxConnector: A-09X
A-09X
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 1 7 . Check t he contin uity between cooling
fan motor drive
control un it connec tor A-1 8 and
body ea
rth.
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 .
AC303534AB
A-18 Connector
(Wiring harness side)
(2)M easu r e the re sist ance between cooling fan
mot o r d r ive cont rol unit conn ecto r A-1 8 te rmina l 1
and body earth .
•Continu i ty exist s .
(3)C onne ct cooling fa n mot o r drive control unit
connector A-18.
Q:Dos e the cont inuity e x ist s ?
YES : Go to S t ep 2 0 .
NO : Go to S t ep 18 .

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 COOLING14-18
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 .

ON-VEHICLE SERVICE
ENGINE COOLING14-23
3. Connect the cooling fan motor drive control unit connector, and disconnect the cooling fan motor
(L.H.) connector.
4. Ensure that the A/C switch is off, and start the engine and run it at idle.
AC303496AB
Cooling fan motor
drive control unit
5.Measure the volt ag e betwee n the cooling f an
motor d r ive cont rol un it side conne ctor t e rminal 1
an d 2.
St andard va lue: 1V or le ss
WARNING
Stay clear of the fan when the fan starts run-
ning.
6. Turn the A/C switch to the "ON" position.
7. Measure the voltage between the cooling fan
motor drive control unit side connector terminal 1
and 2 while the fan is running. The voltage should
repeat the values below.
Standard value:
1. 1 V or less
2. 8.2 ± 0.7 V
3. System voltage ± 2.6 V
8. If the voltage does not repeatedly change as indicated, replace the cooling fan motor drive
control unit. (Refer to
P.14-33) <4G1> (Refer to
P.14-35) <4G6>.
FAN CONTROL RELAY CONTINUITY CHECK
M1141006200280
AC211776
13
4 2
3 4
1
2
AC301712
Fan control relay
AB
Battery
voltageTerminal No.to
be connected
to testerContinuity test
results
Not applied4 − 2Open circuit
Connect
terminal No.1
and battery (
−)
terminal.
Connect
terminal No.3
and battery (+)
terminal.
4 − 2Less than 2
ohms