2005 MITSUBISHI 380 check engine

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.

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.

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.

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.

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.

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.

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.

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.