Engine Cooling: Diagnosis Mitsubishi Eclipse IV рестайлинг

TROUBLESHOOTING STRATEGY

Use these steps to plan your diagnostic strategy. If you follow them carefully, you will be sure to find most of the engine cooling faults.

1. Gather information from the customer
2. Verify that the condition described by the customer exists
3. Find and repair the malfunction by following the «SYMPTOM CHART»(ref-308268-S07387088702009020200000)
4. Verify that the malfunction is eliminated

SYMPTOM CHART

SYMPTOM CHART

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1. STEP 1. Check for coolant leaks. WARNING: When pressure testing the cooling system, slowly release cooling system pressure to avoid getting burned by hot coolant. CAUTION: 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 testing, be careful not to deform the filler neck of the radiator Check that the coolant level is up to the filler neck. Install a radiator 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 Step 2. NO : There is no action to be taken.
2. STEP 2. Retest the system. Q: It there still coolant leakage? YES : Return to Step 1 . NO : The procedure is complete.

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1. 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 «ENGINE COOLANT REPLACEMENT»(ref-308268-S42170210482009020200000) . NO : There is no action to be taken. Go to Step 2.
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. Use a cap adapter to attach the cap to the tester 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 .
3. STEP 3. Check thermostat operation. Refer to «INSPECTION»(ref-308268-S07787807872009020200000) . Q: Does the thermostat operate correctly? YES : Go to Step 4. NO : Replace the thermostat, then go to Step 5 .
4. STEP 4. Check the drive belt for slippage or damage. Refer to «DRIVE BELTS (FOR GENERATOR, POWER STEERING PUMP AND AIR CONDITIONING) (CHECK)»(ref-308257-S06977915122009020200000) . 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.
5. 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.

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TROUBLESHOOTING HINTS

1. Malfunction of fusible link
2. Malfunction of fan control relay
3. Malfunction of MFI relay
4. Malfunction of fan control module
5. Malfunction of ECM < M/T > or PCM < A/T >
6. Damaged wiring harness or connector

DIAGNOSIS

Required Special Tools

1. MB992006: Extra Fine Probe
2. MB991223: Harness Set
3. MB991923: Power Plant ECU Check Harness

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1. STEP 1. Check the circuit at fan control module connector A-22 (terminal 3). Disconnect fan control module connector A-22, and measure at the harness side connector Measure the voltage between terminal number 3 and ground When the ignition switch is turned to the "ON" position, voltage should measure battery positive voltage. Q: Is there voltage battery positive voltage when the ignition switch is turned to the "ON" position? YES : Go to Step 8 . NO : Go to Step 2.
2. STEP 2. Check the fan control relay. Refer to «FAN CONTROL RELAY CONTINUITY CHECK»(ref-308268-S30588409632009020200000) . Q: Is the fan control relay in good condition? YES : Go to Step 3. NO : Replace it, then go to Step 1 .
3. STEP 3. Check the MFI relay. Refer to «FUEL PUMP CONNECTOR DISCONNECTION (HOW TO REDUCE PRESSURIZED FUEL LINES)»(ref-308262-S27274500432009020200000) . Q: Is the MFI relay in good condition? YES : Go to Step 4. NO : Replace it, then go to Step 1 .
4. STEP 4. Check for harness damage between fusible link number 23 and fan control relay connector A-12X (terminal 4). Q: Are the harness wires between fusible link number 23 and fan control relay connector A-12X damaged? YES : Repair or replace them, then go to Step 14 . NO : Go to Step 5.
5. STEP 5. Check for harness damage between fan control relay connector A-12X (terminal 2) and fan control module connector A-22 (terminal 3). Q: Are the harness wires between fan control relay connector A-12X (terminal 2) and fan control module connector A-22 (terminal 3) damaged? YES : Repair or replace them, then go to Step 14 . NO : Go to Step 6.
6. STEP 6. Check intermediate connector A-15 for loose, corroded or damaged terminals, or terminals pushed back in the connector. Q: Are the connectors and terminals in good condition? YES : Go to Step 7. NO : Repair or replace the damaged components. Refer to «HARNESS CONNECTOR INSPECTION»(ref-308258-S34323851462009020200000) .
7. STEP 7. Check for harness damage between MFI relay connector B-16X and fan control relay connector A-12X. Q: Are the harness wires between MFI relay connector B-16X (terminal 4) and fan control relay connector A-12X (terminal 1) damaged? YES : Repair or replace them, then go to Step 14 . NO : Go to Step 8.
8. STEP 8. Check for harness damage between fan control relay connector A-12X (terminal 3) and ground. Q: Are the harness wires between fan control relay connector A-12X (terminal 3) and ground damaged? YES : Repair or replace them, then go to Step 14 . NO : Go to Step 9.
9. STEP 9. Check the circuit at fan control module connector A-22 (Terminal No. 1). Disconnect fan control module connector A-22, and measure at the harness side connector. Measure the resistance between terminal number 1 and ground. Q: Is the resistance less than 2 ohms? YES : Go to Step 11 . NO : Go to Step 10.
10. STEP 10. Check the harness wire between fan control module connector A-22 (terminal 1) and ground. Q: Are the harness wires between fan control module connector A-22 (terminal 1) and ground damaged? YES : Repair or replace them, then go to Step 14 . NO : Go to Step 11.
11. STEP 11. Measure the output circuit voltage at ECM < M/T > or PCM < A/T > connector B-18 (terminal 10) by using check harness special tool MB991923. Disconnect all the connectors from the ECM < M/T > or PCM < A/T >. Connect special tool MB991923 (check harness) between the ECM < M/T > or PCM < A/T > and the body-side harness connector. Start the engine and allow it to idle. Measure the voltage between terminal number 10 and ground. Q: Is the voltage 0.7 volt or more when the radiator fan is operating? YES : Go to Step 13 . NO : Go to Step 12.
12. STEP 12. Check the harness wire between ECM < M/T > or PCM < A/T > connector B-18 and fan control module connector A-22. Q: Are the harness wires between ECM < M/T > or PCM < A/T > connector B-18 (terminal 10) and fan control module connector A-22 (terminal 2) damaged? YES : Repair or replace them, then go to Step 14 . NO : Go to Step 13.
13. STEP 13. Check the fan control module at ECM < M/T > or PCM < A/T > connector B-18 (terminal 10). Do not disconnect ECM < M/T > or PCM < A/T > connector B-18 Pull out terminal number 10 Turn the ignition switch to the "ON" position Q: Do the radiator fan motor and condenser fan motor operate? YES : Replace the ECM < M/T > or PCM < A/T >. Then go to Step 14. NO : Replace the radiator fan motor. Then go to Step 14.
14. STEP 14. Check the symptoms. Q: Do the radiator fan and condenser fan operate correctly? YES : The procedure is complete. NO : Return to Step 1 .

INSPECTION PROCEDURE 4: RADIATOR FAN AND CONDENSER FAN DO NOT CHANGE SPEED OR STOP < 3.8L ENGINE >

Note. If the engine coolant temperature reaches 110°C (230°F) or higher, the radiator fan control runs the radiator fan for up to 5 minutes even after the ignition switch is turned to the "LOCK" (OFF) position [the fan stops its rotation when the engine coolant temperature decreases to 110°C (230°F) or lower.]

1. Malfunction of fan control relay
2. Malfunction of fan control module
3. Malfunction of ECM < M/T > or PCM < A/T >

Required Special Tools

1. MB991223: Harness Set
2. MB991923: Power Plant ECU Check Harness

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1. STEP 1. Check the fan control relay. Refer to «FAN CONTROL RELAY CONTINUITY CHECK»(ref-308268-S30588409632009020200000) . Q: Is the fan control relay in good condition? YES : Go to Step 2. NO : Replace the part, then go to Step 7 .
2. STEP 2. Check the harness wire between fan control relay connector A-12X (terminal 2) and fan control module connector A-22 (terminal 3). Q: Are the harness wires between fan control relay connector A-12X and fan control module connector A-22 damaged? YES : Repair or replace the part, then go to Step 7 . NO : Go to Step 3.
3. STEP 3. Measure the output circuit voltage at ECM < M/T > or PCM < A/T > connector B-18 (terminal 10) by using check harness special tool MB991923. Disconnect all the connectors from the ECM < M/T > or PCM < A/T > Connect special tool MB991923 (check harness) between the ECM < M/T > or PCM < A/T > and the body-side harness connector Start the engine and run it at idle. [Engine coolant temperature: 80°C (176°F) or less] Measure the voltage between terminal number 10 and ground Q: Is the voltage 0 to 0.3 volt when the radiator fan is not operating? YES : Go to Step 7 . NO : Go to Step 4.
4. STEP 4. Check fan control module connector A-22 and ECM < M/T > or PCM < A/T > connector B-18 for loose, corroded or damaged terminals, or terminals pushed back in the connector. Q: Are the connectors in good condition? YES : Go to Step 5. NO : Repair or replace the damaged components. Refer to «HARNESS CONNECTOR INSPECTION»(ref-308258-S34323851462009020200000) .
5. STEP 5. Check the harness wire between ECM < M/T > or PCM < A/T > connector B-18 (terminal 10) and fan control module connector A-22 (terminal 2). Q: Are the harness wires between ECM < M/T > or PCM < A/T > connector B-18 and fan control module connector A-22 damaged? YES : Repair or replace them, then go to Step 7 . NO : Go to Step 6.
6. STEP 6. Check the fan control module at ECM < M/T > or PCM < A/T > connector B-18. Disconnect ECM < M/T > or PCM < A/T > connector B-18. Pull out the pin 10 and connect it to the body ground. Reconnect ECM < M/T > or PCM < A/T > connector B-18 with pin 10 still removed. Turn the ignition switch to the " ON" position Q: Do the radiator fan motor and condenser fan motor stop? YES : Replace the ECM < M/T > or PCM < A/T >. Then go to Step 7. NO : Replace the radiator fan motor. Then go to Step 7.
7. STEP 7. Check the symptoms. Q: Do the radiator fan and condenser fan operate correctly? YES : The procedure is complete. NO : Return to Step 1 .

TROUBLESHOOTING HINT

Malfunction of radiator fan motor

Replace the radiator fan motor.

1. Malfunction of condenser fan motor
2. Malfunction of fan control module

1. STEP 1. Check the condenser fan motor. Refer to «CONDENSER AND CONDENSER FAN MOTOR»(ref-308259-S21307003752009020200000) . Q: Is the condenser fan motor in good condition? YES : Go to Step 2. NO : Replace the condenser fan motor, then go to Step 3 .
2. STEP 2. Check the fan control module. Refer to «FAN CONTROL MODULE CHECK < 3.8L ENGINE >»(ref-308268-S38392584492009020200000) . Q: Is the fan control module in good condition? YES : Go to Step 3. NO : Replace the radiator fan motor, then go to Step 3.
3. STEP 3. Check the symptoms. Q: Does the condenser fan operate correctly? YES : The procedure is complete. NO : Return to Step 1 .

ENGINE COOLANT CONCENTRATION TEST

Refer to RECOMMENDED LUBRICANTS AND LUBRICANT CAPACITIES TABLE .