Mitsubishi Colt Ralliart. Manual - part 87

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4A9>

13A-302

Inspection Procedure 25: Fan control relay system

OPERATION

• The battery voltage is applied to the cooling fan 

control relay coil (terminal No. 1) from the ignition 
switch.

• The engine-ECU <M/T> or engine-CVT-ECU 

<CVT> (terminal No. 95) turns on the switch of 
the power transistor on the unit, and then turns 
on the switch of the relay by applying the electri-
cal current to the cooling fan control relay coil.

• When the cooling fan control relay is in ON posi-

tion, the battery voltage is applied to the cooling 
fan motor (terminal No. 1) from the cooling fan 
control relay (terminal No. 4).

FUNCTION

• When the cooling fan control relay is in ON posi-

tion, the fan motor rotates.

AK402704

M

3

1

2

4

1 2

3 4

R

92 93 94 95969798

77 78 79 808182838485868788899091

99

100

107 108 109 110 111112113114115116117118119120121
122 123 124 125126127128129130131132133134135136

101102103104105106

71 72

73 74

75 76

6

Cooling 
fan 
motor 

J/C

Cooling fan 
control
relay 

Engine-ECU <M/T> or
engine-CVT-ECU <CVT>

B-109

R-L

B-110

B-108

3

1

1

R

Fusible link

3

40A

L

B

J/B

14

95

B-130

1

3

L-R

Ignition switch (IG2)

41

7.5A

1

2

2

A-08

B-114

A-20

MU802223

A-31

AD

Cooling Fan Control Relay Circuit

4

2

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  Pu: Purple

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4A9>

13A-303

PROBABLE CAUSES

• Failed cooling fan control relay

• Failed cooling fan motor

• Open/short/damaged circuit in cooling fan control 

relay circuit or loose connector contact

• Failed engine-ECU <M/T> or engine-CVT-ECU 

<CVT>

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-114 cooling fan 
control relay connector

Q: Is the check result normal?

YES : 

Go to Step 2 .

NO : 

Repair or replace the connector.

STEP 2. Check cooling fan control relay.

• Check cooling fan control relay (Refer to GROUP 

14 

− On-vehicle Service − Fan Control Relay 

Continuity Check 

P.14-8

).

Q: Is the check result normal?

YES : 

Go to Step 3 .

NO : 

Replace fan control relay.

STEP 3. Connector check: A-20 cooling fan 
motor connector

Q: Is the check result normal?

YES : 

Go to Step 4 .

NO : 

Repair or replace the connector.

STEP 4. Check cooling fan motor.

• Check cooling fan motor (Refer to GROUP 14 − 

On-vehicle Service 

− Cooling Fan Motor Check 

P.14-8

).

Q: Is the check result normal?

YES : 

Go to Step 5 .

NO : 

Replace cooling fan motor.

AK402058

3

2

1

4

AC

B-114
J/B side 
connector

Connector: B-114

J/B (front side)

B-114

AK402059

2 1

4 3

AC

A-20 Harness
side connector

A-20

Connector: A-20

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4A9>

13A-304

STEP 5. Perform voltage measurement at B-114 
cooling fan control relay connector.

• Disconnect connector and measure at harness 

side.

• Voltage between terminal No. 3 and earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 6 .

NO : 

Check intermediate connector B-108, and 

repair if necessary. If intermediate 
connector is normal, check and repair 
harness between B-114 (terminal No. 3) 
cooling fan control relay connector and 
battery.

• Check power supply line for 

open/short circuit.

STEP 6. Perform voltage measurement at B-114 
fan control relay connector.

• Disconnect connector and measure at harness 

side.

• Ignition switch: ON

• Voltage between terminal No. 1 and earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 8 .

NO : 

Go to Step 7 .

AK402058

3

2

1

4

AC

B-114
J/B side 
connector

Connector: B-114

J/B (front side)

B-114

AK402058

3

2

1

4

AC

B-114
J/B side 
connector

Connector: B-114

J/B (front side)

B-114

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4A9>

13A-305

STEP 7. Connector check: B-141 ignition switch 
connector

Q: Is the check result normal?

YES : 

Check intermediate connector B-130 and 

repair if necessary. If intermediate 
connector is normal, check and repair 
harness between B-114 (terminal No. 1) 
cooling fan control relay connector and 
B-141 (terminal No. 4) ignition switch 
connector.

• Check power supply line for 

open/short circuit.

NO : 

Repair or replace the connector.

STEP 8. Check harness between battery and 
B-114 (terminal No. 3) cooling fan control relay 
connector.

NOTE: Before checking harness, check intermediate 
connector B-108, and repair if necessary.

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

Go to Step 9 .

NO : 

Repair the damaged harness wire.

AK402054

B-141

AC

Connector: B-141

1

2

3

4

5

6

B-141 Harness
side connector

AK402058

3

2

1

4

AC

B-114
J/B side 
connector

Connector: B-114

J/B (front side)

B-114

AK402058

3

2

1

4

AC

B-114
J/B side 
connector

Connector: B-114

J/B (front side)

B-114

Main

Index

Group

TOC