check engine MITSUBISHI 380 2005 Owner's Guide
Page 916 of 1500
14-1
GROUP 14
ENGINE COOLING
CONTENTS
GENERAL DESCRIPTION. . . . . . . . .14-2
SPECIAL TOOL . . . . . . . . . . . . . . . . .14-2
ENGINE COOLING DIAGNOSIS . . . .14-2
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . 14-2
TROUBLESHOOTING STRATEGY . . . . . . 14-2
SYMPTOM CHART. . . . . . . . . . . . . . . . . . . 14-3
SYMPTOM PROCEDURES . . . . . . . . . . . . 14-3
ON-VEHICLE SERVICE . . . . . . . . . . .14-26
ENGINE COOLANT LEAK CHECK . . . . . . 14-26
RADIATOR CAP PRESSURE CHECK . . . . 14-27
ENGINE COOLANT REPLACEMENT . . . . 14-27
ENGINE COOLANT CONCENTRATION TEST14-29
FAN CONTROLLER CHECK . . . . . . . . . . . 14-29
FAN CONTROL RELAY CONTINUITY CHECK14-31
RADIATOR . . . . . . . . . . . . . . . . . . . . .14-32
REMOVAL AND INSTALLATION . . . . . . . . 14-32
THERMOSTAT . . . . . . . . . . . . . . . . . .14-35
REMOVAL AND INSTALLATION . . . . . . . . 14-35
INSPECTION. . . . . . . . . . . . . . . . . . . . . . . . 14-38
WATER PUMP . . . . . . . . . . . . . . . . . .14-39
REMOVAL AND INSTALLATION . . . . . . . . 14-39
WATER HOSE AND WATER PIPE . .14-40
REMOVAL AND INSTALLATION . . . . . . . . 14-40
INSPECTION. . . . . . . . . . . . . . . . . . . . . . . . 14-41
SPECIFICATIONS . . . . . . . . . . . . . . .14-42
FASTENER TIGHTENING
SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . 14-42
SERVICE SPECIFICATION . . . . . . . . . . . . 14-43
CAPACITIES . . . . . . . . . . . . . . . . . . . . . . . . 14-43
SEALANTS . . . . . . . . . . . . . . . . . . . . . . . . . 14-43
Page 918 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-3
SYMPTOM CHARTM1141005600393
SYMPTOM PROCEDURES
INSPECTION PROCEDURE 1: Coolant Leak
DIAGNOSIS
STEP 1. Check for coolant leaks.
When pressure testing the cooling system, slowly
release cooling system pressure to avoid being
burned by hot coolant.
Be sure to completely clean away any moisture from
the places checked.
When the tester is removed, be careful not to spill any
coolant.
When installing and removing the tester and when test-
ing, be careful not to deform the filler neck of the radia-
tor.
Check that the coolant level is up to the filler neck. Install a radi-
ator tester and apply 160 kPa (23 psi) pressure, and then check
for leakage from the radiator hose or connections.
Q: Is leakage present from the radiator hose or
connections?
YES : Repair or replace the appropriate part, then go to
St e p 2 .
NO : There is no action to be taken.
STEP 2. Retest the system.
Q: Is there still coolant leakage?
YES : Return to Step 1.
NO : The procedure is complete. SYMPTOM INSPECTION
PROCEDUREREFERENCE
PA G E
Coolant leak 1
14-3
Engine overheating 2
14-4
Radiator fan and condenser fan do not operate 3
14-4
Radiator fan and condenser fan do not change speed or stop 4
14-20
Radiator fan does not operate 5
14-25
Condenser fan does not operate 6
14-25
Page 919 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-4
INSPECTION PROCEDURE 2: Engine Overheating
DIAGNOSIS
STEP 1. Remove the radiator cap and check for coolant
contamination.
Q: Is the coolant contaminated with rust and oil?
YES : Replace it. Refer to P.14-27.
NO : There is no action to be taken. Go to Step 2.
STEP 2. Check the radiator cap valve opening pressure.
NOTE: Be sure that the cap is clean before testing. Rust or
other foreign material on the cap seal will cause an improper
reading.
(1) Use a cap adapter to attach the cap to the tester.
(2) Increase the pressure until the gauge indicator stops
moving.
Minimum limit: 83 kPa (12 psi)
Standard value: 93
123 kPa (14 18 psi)
Q: Does the reading remain at or above the minimum limit?
YES : Go to Step 3.
NO : Replace the radiator cap. Then go to Step 5.
STEP 3. Check thermostat operation.
Refer to 38.
Q: Does the thermostat operate correctly?
YES : Go to Step 4.
NO : Replace the thermostat, then go to Step 5.
STEP 4. Check the drive belt for slippage or damage.
Refer to GROUP 00, Maintenance Service
Drive Belts
(Check Condition). <3.8L Engine>39 .
Q: Is the drive belt loose or damaged?
YES : Adjust or replace the drive belt, then go to Step 5.
NO : There is no action to be taken.
STEP 5. Retest the system.
Check the engine coolant temperature.
Q: Is the engine coolant temperature abnormally high?
YES : Return to Step 2.
NO : The procedure is complete.
Page 921 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-6
DIAGNOSIS
STEP 1. Measure the power supply voltage at fan
controller connector A-24.
(1) Disconnect fan controller connector A-24 and measure
wiring harness side connector.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between fan controller connector A-24
terminal 3 and body earth.
The voltage should measure system voltage.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Connect fan controller connector A-24.
Q: Is the measured voltage system voltage?
YES : Go to Step 17.
NO : Go to Step 2.
STEP 2. Check the fan controller connector A-24.
Q: Is the connector in good condition?
YES : Go to Step 3.
NO : Repair or replace the connector. Then go to Step 24.
Page 922 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-7
STEP 3. Check the fusible link No.2.
Q: Is the fusible link No.2 in good condition?
YES : Go to Step 4.
NO : Replace the fusible link No.2. Then go to Step 24.
STEP 4. Measure the power supply voltage at fan control
relay connector A-10X.
(1) Disconnect fan control relay connector A-10X (remove the
fan control relay) and measure relay box side connector.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between fan control relay connector
A-10X terminal 4 and body earth.
The voltage should measure system voltage.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Connect fan control relay connector A-10X (install the fan
control relay).
Q: Is the measured voltage system voltage?
YES : Go to Step 7.
NO : Go to Step 5.
Page 923 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-8
STEP 5. Check the fan control relay connector A-10X.
Q: Is the connector in good condition?
YES : Go to Step 6.
NO : Repair the connector or replace the relay box. Then
go to Step 24.
STEP 6. Check the harness wire between fusible link No.2
and fan control relay connector A-10X terminal 4.
Q: Is the harness wire in good condition?
YES : An intermittent malfunction is suspected (Refer to
GROUP 00 - How to use troubleshooting 00-7).
NO : Repair the damaged harness wire. Then go to Step
24.
STEP 7. Check the fan control relay.
Refer to 14-31.
Q: Is the fan control relay in good condition?
YES : Go to Step 8.
NO : Replace the fan control relay. Then go to Step 24.
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ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-9
STEP 8. Check the fan control relay connector A-10X.
Q: Is the connector in good condition?
YES : Go to Step 9.
NO : Repair the connector or replace the relay box. Then
go to Step 24.
STEP 9. Check the harness wire between fan control relay
connector A-10X terminal 2 and fan controller connector
A-24 terminal 3.
Q: Is the harness wire in good condition?
YES : Go to Step 10.
NO : Repair the damaged harness wire. Then go to Step
24.
Page 926 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-11
STEP 11. Check the ECU connector B-21, intermediate
connector A-13 and fan control relay connector A-10X.
Q: Are there connectors in good condition?
YES : Go to Step 12.
NO : Repair or replace the connector. Then go to Step 24.
Page 927 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-12
STEP 12. Check the harness wire between intermediate
connector A-13 terminal 2 and fan control relay connector
A-10X terminal 3.
Q: Are these harness wires in good condition?
YES : An intermittent malfunction is suspected (Refer to
00-7).
NO : Repair the damaged harness wire. Then go to Step
24.
Page 928 of 1500
ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-13
STEP 13. Check the continuity between fan control relay
connector A-10X and body earth.
(1) Disconnect fan control relay connector A-10X (remove the
fan control relay) and measure relay box side connector.
(2) Measure the resistance between fan control relay connector
A-10X terminal 1 and body earth.
Continuity exists.
(3) Connect fan control relay connector A-10X (install the fan
control relay).
Q: Does the continuity exists?
YES : An intermittent malfunction is suspected (Refer to
00-7).
NO : Go to Step 14.
STEP 14. Check the fan control relay connector A-10X.
Q: Is the connector in good condition?
YES : Go to Step 15.
NO : Repair the connector or replace the relay box. Then
go to Step 24.