INSPECTION
OPERATING CONDITION
| Vehicle speed | A/C compressor load | Engine coolant temperature | ||
|---|---|---|---|---|
| Increase: 94°C (201°F) or less Decrease: 91°C (196°F) or less | Increase: 95 - 96°C (203 - 205°F) Decrease: 92 - 94°C (198 - 201 °F) | Increase: 97°C (207°F) or more Decrease: 95°C (203°F) or more | ||
| Radiator fan operation | Radiator fan operation | Radiator fan operation | ||
| During acceleration: 19 km/h (12 MPH) or less During deceleration: 10 km/h (6 MPH) or less | OFF | OFF | Low-Speed | High-Speed |
| Low | Low-Speed | Low-Speed | High-Speed | |
| High | High-Speed | High-Speed | High-Speed | |
| During acceleration: 20 - 69 km/h (12 - 43 MPH) During deceleration: 11 - 64 km/h (7 - 40 MPH) | OFF | OFF | Low-Speed | High-Speed |
| Low | High-Speed | High-Speed | High-Speed | |
| High | High-Speed | High-Speed | High-Speed | |
| During acceleration: 70 - 105 km/h (43 - 65 MPH) During deceleration: 65 - 103 km/h (40 - 64 MPH) | OFF | OFF | Low-Speed | High-Speed |
| Low | High-Speed | High-Speed | High-Speed | |
| High | High-Speed | High-Speed | High-Speed | |
| During acceleration: 106 km/h (66 MPH) or more During deceleration: 104 km/h (65 MPH) or more | OFF | OFF | High-Speed | High-Speed |
| Low | High-Speed | High-Speed | High-Speed | |
| High | High-Speed | High-Speed | High-Speed | |
OPERATING CONDITION REFERENCE
DIAGNOSIS
Radiator main fan and radiator sub fans do not rotate under the above operating conditions.
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK OPERATION OF RADIATOR FAN. Connect the delivery (test) mode connector. Turn the ignition switch to ON. Using the Subaru Select Monitor, check the forced operation of the radiator fan relay. NOTE: When performing a forced operation radiator fan relay check using the Subaru Select Monitor, the radiator main fan and radiator sub fan will repeat low speed revolution --> high speed revolution --> OFF in this order. Subaru Select Monitor Refer to "Compulsory Valve Operation Check Mode" for detailed procedures. Ref. to COMPULSORY VALVE OPERATION CHECK MODE . | Do the radiator main fans and radiator sub fans rotate at low speed? | Go to step 2 . | Go to step 3 . |
| 2 CHECK OPERATION OF RADIATOR FAN. Connect the delivery (test) mode connector. Turn the ignition switch to ON. Perform the compulsory operation check for the radiator fan relay using Subaru Select Monitor. NOTE: When performing a forced operation radiator fan relay check using the Subaru Select Monitor, the radiator main fan and radiator sub fan will repeat low speed revolution --> high speed revolution --> OFF in this order. Subaru Select Monitor Refer to "Compulsory Valve Operation Check Mode" for detailed procedures. Ref. to COMPULSORY VALVE OPERATION CHECK MODE . | Do the radiator main fans and radiator sub fans rotate at high speed? | Radiator main fan system is normal. | Go to step 27 . |
| 3 CHECK POWER SUPPLY TO SUB FAN RELAY. Turn the ignition switch to OFF. Remove the sub fan relay from the relay holder. Measure the voltage between the sub fan relay terminal and chassis ground. Connector & terminal (F27) No. 10 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 4 . | Go to step 5 . |
| 4 CHECK POWER SUPPLY TO SUB FAN RELAY. Turn the ignition switch to ON. Measure the voltage between the sub fan relay terminal and chassis ground. Connector & terminal (F27) No. 13 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 7 . | Go to step 6 . |
| 5 CHECK FUSE. Turn the ignition switch to OFF. Remove the fuse No. 3. Check the condition of fuse. | Is the fuse blown out? | Replace the fuse. | Repair the power supply line. |
| 6 CHECK FUSE. Turn the ignition switch to OFF. Remove the fuse No. 22. Check the condition of fuse. | Is the fuse blown out? | Replace the fuse. | Repair the power supply line. |
| 7 CHECK SUB FAN RELAY. Turn the ignition switch to OFF. Measure the resistance between sub fan relay terminals. Terminals No. 10 - No. 11 | Is the resistance 1 Mohms or more? | Go to step 8 . | Replace the sub fan relay. |
| 8 CHECK SUB FAN RELAY. Connect the battery to terminals No. 12 and No. 13 of the sub fan relay. Measure the resistance between sub fan relay terminals. Terminals No. 10 - No. 11 | Is the resistance less than 1 ohms? | Go to step 9 . | Replace the sub fan relay. |
| 9 CHECK HARNESS BETWEEN SUB FAN RELAY TERMINAL AND SUB FAN MOTOR CONNECTOR. Disconnect the connector from the sub fan motor. Measure the resistance of harness between the sub fan relay terminal and sub fan motor connector. Connector & terminal (F16) No. 1 - (F27) No. 11 | Is the resistance less than 1 ohms? | Go to step 10 . | Repair the open circuit of harness between sub fan relay terminal and sub fan motor connector. |
| 10 CHECK HARNESS BETWEEN SUB FAN MOTOR CONNECTOR AND MAIN FAN RELAY 2 CONNECTOR. Remove main fan relay 2 from the relay holder. Measure the resistance of harness between sub fan motor connector and main fan relay 2 connector. Connector & terminal (F16) No. 2 - (F27) No. 18 | Is the resistance less than 1 ohms? | Go to step 11 . | Repair the open circuit of the harness between sub fan motor connector and main fan relay 2 connector. |
| 11 CHECK POOR CONTACT. Check poor contact of sub fan motor connector. | Is there poor contact of the sub fan motor connector? | Repair the poor contact of sub fan motor connector. | Go to step 12 . |
| 12 CHECK SUB FAN MOTOR. Connect the battery positive (+) terminal to terminal No. 1 of the sub fan motor, and the ground (-) terminal to terminal No. 2. | Does the radiator sub fan rotate? | Go to step 13 . | Replace the sub fan motor. |
| 13 CHECK MAIN FAN RELAY 2. Measure the resistance of main fan relay 2. Terminals No. 21 - No. 18 | Is the resistance less than 1 ohms? | Go to step 14 . | Replace the main fan relay 2. |
| 14 CHECK HARNESS BETWEEN MAIN FAN RELAY 2 AND MAIN FAN MOTOR CONNECTOR. Disconnect the connector from the main fan motor. Measure the resistance of the harness between main fan relay 2 terminal and main fan motor connector. Connector & terminal (F17) No. 1 - (F27) No. 21 | Is the resistance less than 1 ohms? | Go to step 15 . | Repair the open circuit of the harness between main fan relay 2 terminal and main fan motor connector. |
| 15 CHECK MAIN FAN MOTOR AND GROUND CIRCUIT. Measure the resistance between main fan motor connector and chassis ground. Connector & terminal (F17) No. 2 - Chassis ground | Is the resistance less than 5 ohms? | Go to step 16 . | Repair the open circuit of the harness between main fan motor connector and chassis ground. |
| 16 CHECK POOR CONTACT. Check poor contact of main fan motor connector. | Is there poor contact of the main fan motor connector? | Repair the poor contact of main fan motor connector. | Go to step 17 . |
| 17 CHECK MAIN FAN MOTOR. Connect the battery positive (+) terminal to terminal No. 1 of the main fan motor, and the ground (-) terminal to terminal No. 2. | Does the radiator main fan rotate? | Go to step 18 . | Replace the main fan motor. |
| 18 CHECK HARNESS BETWEEN SUB FAN RELAY AND ECM. Disconnect the connectors from ECM. Measure the resistance between the sub fan relay terminal and ECM connector. Connector & terminal (B136) No. 18 - (F27) No. 12 | Is the resistance less than 1 ohms? | Go to step 19 . | Repair the open circuit of harness between sub fan relay terminal and ECM. |
| 19 CHECK POOR CONTACT. Check for poor contact of ECM connector. | Is there poor contact of ECM connector? | Repair the poor contact of ECM connector. | Check the DTC. Repair the trouble cause. Ref. to READ DIAGNOSTIC TROUBLE CODE (DTC) . |
| 20 CHECK MAIN FAN RELAY 1. Turn the ignition switch to OFF. Remove main fan relay 1 from the main fuse box. Measure the resistance of terminal in main fan relay 1 switch. | Is the resistance 1 Mohms or more? | Go to step 21 . | Replace the main fan relay 1. |
| 21 CHECK MAIN FAN RELAY 1. Connect the main fan relay 1 coil side terminal to the battery. Measure the resistance between terminals of main fan relay 1 switch. | Is the resistance less than 1 ohms? | Go to step 22 . | Replace the main fan relay 1. |
| 22 CHECK HARNESS BETWEEN MAIN FAN RELAY 1 AND MAIN FAN MOTOR CONNECTOR. Disconnect the connector from the main fan motor. Measure the resistance of the harness between main fan relay 1 terminal and main fan motor connector. Connector & terminal (F17) No. 1 - (F36) No. 6 | Is the resistance less than 1 ohms? | Go to step 23 . | Repair the open circuit of the harness between main fan relay 1 terminal and main fan motor connector. |
| 23 CHECK HARNESS BETWEEN MAIN FAN RELAY 1 AND ECM. Disconnect the connectors from ECM. Measure the resistance between main fan relay 1 terminal and ECM connector. Connector & terminal (B136) No. 29 - (B143) No. 7 | Is the resistance less than 1 ohms? | Go to step 24 . | Repair the open circuit of the harness between main fan relay 1 terminal and ECM. |
| 24 CHECK HARNESS BETWEEN MAIN FAN RELAY 2 AND ECM. Measure the resistance between main fan relay 2 terminal and ECM connector. Connector & terminal (B136) No. 29 - (F27) No. 22 | Is the resistance less than 1 ohms? | Go to step 25 . | Repair the open circuit of the harness between main fan relay 2 terminal and ECM. |
| 25 CHECK FUSE. Turn the ignition switch to OFF. Remove the fuse No. 2 and 26. Check the condition of fuse. | Is the fuse blown out? | Replace the fuse. | Go to step 26 . |
| 26 CHECK POOR CONTACT. Check for poor contact of ECM connector. | Is there poor contact of ECM connector? | Repair the poor contact of ECM connector. | Repair the power supply circuit to the main fuse box. |
| 27 CHECK OPERATION OF RADIATOR FAN. If the both fans do not rotate at high speed in the condition of step 2, check whether the radiator sub fan is rotating. | Does the radiator sub fan rotate? | Go to step 20 . | Go to step 28 . |
| 28 CHECK GROUND CIRCUIT OF MAIN FAN RELAY 2. Remove main fan relay 2 from the relay holder. Measure the resistance between main fan relay 2 terminal and chassis ground. Connector & terminal (F27) No. 19 - Chassis ground | Is the resistance less than 1 ohms | Go to step 29 . | Repair the open circuit of harness between main fan relay 2 and chassis ground. |
| 29 CHECK POWER SUPPLY TO MAIN FAN RELAY 2. Turn the ignition switch to ON. Measure the voltage between main fan relay 2 terminal and chassis ground. Connector & terminal (F27) No. 20 (+) - Chassis ground (-) | Is the voltage 10 V or more? | Go to step 30 . | Repair the power supply line. |
| 30 CHECK MAIN FAN RELAY 2. Turn the ignition switch to OFF. Remove the main fan relay 2. Measure the resistance of main fan relay 2. Terminals (F27) No. 18 - (F27) No. 19 | Is the resistance 1 Mohms or more? | Go to step 31 . | Replace the main fan relay 2. |
| 31 CHECK MAIN FAN RELAY 2. Connect the battery to terminals No. 20 and No. 22 of the main fan relay 2. Measure the resistance of main fan relay 2. Terminals (F27) No. 18 - (F27) No. 19 | Is the resistance less than 1 ohms? | Go to step 23 . | Replace the main fan relay 2. |
| NOTE |
|---|
| When performing a forced operation radiator fan relay check using the Subaru Select Monitor, the radiator main fan and radiator sub fan will repeat low speed revolution --> high speed revolution --> OFF in this order. Subaru Select Monitor Refer to "Compulsory Valve Operation Check Mode" for detailed procedures. Ref. to COMPULSORY VALVE OPERATION CHECK MODE . |
| NOTE |
|---|
| When performing a forced operation radiator fan relay check using the Subaru Select Monitor, the radiator main fan and radiator sub fan will repeat low speed revolution --> high speed revolution --> OFF in this order. Subaru Select Monitor Refer to "Compulsory Valve Operation Check Mode" for detailed procedures. Ref. to COMPULSORY VALVE OPERATION CHECK MODE . |
DIAGNOSIS PROCEDURE CHART
Scheme 81
- Set the vehicle on a lift.
- Lift up the vehicle.
- Remove the under cover.
- Remove the drain plug to drain engine coolant into container. NOTE: Remove the coolant filler tank cap so that engine coolant will drain faster.
- Install the drain plug.
- Install the under cover.
Scheme 82
- Pour cooling system conditioner through the filler neck. Cooling system protective agent: Refer to "SPECIFICATION" for cooling system protective agent. Ref. to «SPECIFICATION»(ref-357239-S10603140542010031100000) , General Description.
- Fill the engine coolant into coolant filler tank up to the filler neck position. Recommended engine coolant: Refer to "SPECIFICATION" for recommended engine coolant. Ref. to «SPECIFICATION»(ref-357239-S10603140542010031100000) , General Description. Engine coolant level: Refer to "SPECIFICATION" for engine coolant level. Ref. to «SPECIFICATION»(ref-357239-S10603140542010031100000) , General Description. Engine coolant concentration: Refer to "ADJUSTMENT" for the recommended engine coolant concentration. Ref. to «ADJUSTMENT»(ref-357239-S01812303152010031100000) , Engine Coolant. CAUTION: Do not confuse the cap of coolant filler tank and cap of radiator. NOTE: When pouring the engine coolant, the radiator side cap must not be removed. The SUBARU Super Coolant contains antifreeze and anti-rust agents, and is especially made for Subaru engines with an aluminum cylinder block. Always use SUBARU Super Coolant, since other coolant may cause corrosion.
- Fill engine coolant into the reservoir tank up to "FULL" level.
- Close the coolant filler tank cap, and start the engine. Race 5 to 6 times at 3,000 RPM or less, then stop the engine. (Complete this operation within 40 seconds.)
- Wait for one minute after the engine stops, then open the coolant filler tank cap. If the engine coolant level drops, add engine coolant into the coolant filler tank up to the filler neck position.
- Perform the procedures 4) and 5) again.
- Install the coolant filler tank cap and reservoir tank cap properly.
- Start the engine and operate the heater at maximum hot position and the blower speed setting to "LO".
- Run the engine at 2,000 RPM or less until radiator fan starts and stops. NOTE: Be careful with the engine coolant temperature gauge to prevent overheating.
- Stop the engine and wait until the engine coolant temperature lowers to 30°C (86°F) or less.
- Open the coolant filler tank cap. If the engine coolant level drops, add engine coolant into the coolant filler tank up to the filler neck position and the reservoir tank to "FULL" level.
- Install the coolant filler tank cap and reservoir tank cap properly.
- Set the heater setting to maximum hot position and the blower speed setting to "LO" and start the engine. Perform racing at 3,000 RPM or less. If the flowing sound is heard from heater core, repeat the procedures from step 9).
Replace the thermostat if the valve does not close completely at an ambient temperature or if the following test shows unsatisfactory results.
- Inspection method
Immerse the thermostat and a thermometer in water. Raise water temperature gradually, and measure the temperature and valve lift when the valve begins to open and when the valve is fully opened. During the test, agitate the water for even temperature distribution. The measured value should meet the specification.
Note. Leave the thermostat in the boiling water for five minutes or more before measuring the valve lift. Hold the thermostat with a wire or the like to avoid contacting the container.
Starting temperature to open: 76 - 80°C (169 - 176°F)
Full open temperature: 91°C (196°F)
Total valve lift: 9.0 mm (0.354 in) or more
Scheme 83
Make sure the engine coolant level is between "FULL" and "LOW".
| Trouble | Possible cause | Corrective action |
|---|---|---|
| Over-heating | A. Insufficient engine coolant | Replenish engine coolant, inspect for leakage, and repair it if necessary. |
| B. Loose timing belt | Repair or replace timing belt tensioner. | |
| C. Oil on timing belt | Replace. | |
| D. Malfunction of thermostat | Replace. | |
| E. Malfunction of water pump | Replace. | |
| F. Clogged engine coolant passage | Clean. | |
| G. Improper ignition timing | Inspect and repair ignition control system. Ref. to PROCEDURE , Basic Diagnostic Procedure. | |
| H. Clogged or leaking radiator | Clean, repair or replace. | |
| I. Defective radiator fan | Replace. | |
| J. Improper engine oil in engine coolant | Replace the engine coolant. If ineffective, check, repair or replace engine components. | |
| K. Air/fuel mixture ratio too lean | Inspect and repair the fuel injection system. Ref. to PROCEDURE , Basic Diagnostic Procedure. | |
| L. Excessive back pressure in exhaust system | Clean or replace. | |
| M. Insufficient clearance between piston and cylinder | Adjust or replace. | |
| N. Slipping clutch | Repair or replace. | |
| O. Dragging brake | Adjust. | |
| P. Defective radiator fan | Inspect the radiator fan relay, engine coolant temperature sensor or fan motor and replace them. | |
| Over-cooling | A. Ambient temperature extremely low | Partly cover radiator front area. |
| B. Defective thermostat | Replace. | |
| Engine coolant leaks | A. Loosened or damaged connecting units on hoses | Repair or replace. |
| B. Leakage from water pump | Replace. | |
| C. Leakage from water pipe | Repair or replace. | |
| D. Leakage around cylinder head gasket | Retighten cylinder head bolts or replace cylinder head gasket. | |
| E. Damaged or cracked cylinder head and cylinder block | Repair or replace. | |
| F. Damaged or cracked thermostat cover | Repair or replace. | |
| G. Leakage from radiator | Repair or replace. | |
| Noise | A. Timing belt problem | Replace. |
| B. Defective radiator fan | Replace. | |
| C. Defective water pump bearing | Replace water pump. | |
| D. Defective water pump mechanical seal | Replace water pump. |
ENGINE COOLING SYSTEM TROUBLE REFERENCE