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Engine Cooling System: Diagnosis Toyota Highlander I

Cooling System (Mechanical) 16 illustrations ~1950 words

ON-VEHICLE INSPECTION

Note. It is normal that the cooling fan sometime rotates when the ignition switch is turned from ACC to ON.

  1. Check cooling fan operation with low temperature (below 83°C (181°F)) Turn the ignition switch ON. Check that the cooling fan stops. If not, check the cooling fan relay and water temperature sensor, and check for disconnection of connectors or wire break between the cooling fan relay and water temperature sensor. Disconnect the water temperature sensor connector. Check that the cooling fan rotates. If not, check the fuses, cooling fan relay, engine ECU and cooling fan, and check for a short circuit between the cooling fan relay and water temperature sensor. Reconnect the water temperature sensor connector. .
  2. Check cooling fan operation with high temperature (above 98°C (208°F)) . Start the engine, and raise coolant temperature to above 98°C (208°F). Check that the cooling fan rotates. If not, replace the water temperature sensor.
  3. Inspect cooling fan . Disconnect the cooling fan connector. Connect battery and ammeter to the cooling fan connector. Check that the cooling fan rotates smoothly, and check the reading on the ammeter. Standard amperage: 80W TYPE 5.2 - 8.2 A at 20°C (68°F) 120W TYPE 7.6 - 10.6 A at 20°C (68°F) Reconnect the cooling fan connector.

Scheme 6

Scheme 6: INSPECTION
Scheme 6: INSPECTION
  1. Cooling Fan Relay Inspect the cooling fan relay continuity. Using an ohmmeter, check that there is continuity between terminals 1 and 2. If there is no continuity, replace the relay. Check that there is no continuity between terminals 3 and 5. If there is continuity, replace the relay. Apply battery voltage across terminals 1 and 2. Using an ohmmeter, check that there is continuity between terminals 3 and 5. If there is no continuity, replace the relay.

Scheme 7

Scheme 7: REPLACEMENT
Scheme 7: REPLACEMENT

Scheme 8

Scheme 8
Scheme 8

Scheme 9

Scheme 9
Scheme 9

Scheme 10

Scheme 10
Scheme 10

Scheme 11

Scheme 11
Scheme 11
  1. Drain coolant (See «COOLANT (2AZ-FE)»(ref-179473-S18914038582005070800000) ).
  2. Remove generator assy (See «GENERATOR ASSEMBLY»(ref-173287-S32066356372005042700000) ).
  3. Remove water pump pulley. Using SST, remove 4 bolts and pump pulley. SST 09960-10010 (09962-01000, 09963-00700) Disconnect the crankshaft position sensor wire harness clamp.
  4. Remove water pump assy. Remove 4 bolts, 2 nuts, bracket and water pump.
  5. Install water pump assy. Remove any old packing (FIPG) material from the contact surface. Apply seal packing to the water pump (Scheme 9) Seal packing: Part No. 08826-00080 or equivalent NOTE: Remove any oil from the contact surface. install the water pump within 5 minutes after applying. Do not put into engine oil within 2 hours after installing. Install the water pump and bracket with 4 bolts and 2 nuts. Torque: 9.0 N.m (92 kgf.cm, 80 in.lbf) Connect the crankshaft position sensor wire harness clamp.
  6. Install water pump pulley. Using SST, install the pump pulley with 4 bolts. SST 09960-10010 (09962-01000, 09963-00700) Torque: 26 N.m (265 kgf.cm, 19 ft.lbf)
  7. Add coolant (See «COOLANT (2AZ-FE)»(ref-179473-S18914038582005070800000) ).
  8. Inspect coolant leaks (See «COOLING SYSTEM (2AZ-FE)»(ref-179473-S39267686102005070800000) ).

Scheme 12

Scheme 12: INSPECTION
Scheme 12: INSPECTION
  1. Inspect water pump assy . Visually check the drain hole coolant leakage. Turn the pulley, and check that the water pump bearing moves smoothly and quietly.

Scheme 13

Scheme 13: REPLACEMENT
Scheme 13: REPLACEMENT

Scheme 14

Scheme 14
Scheme 14
  1. Drain coolant (See «COOLANT (2AZ-FE)»(ref-179473-S18914038582005070800000) ) .
  2. Remove generator assy (See «GENERATOR ASSEMBLY»(ref-173287-S32066356372005042700000) ) .
  3. Remove water inlet . Remove 2 nuts, and disconnect the water inlet from the cylinder block.
  4. Remove thermostat .
  5. Install thermostat . Install a new gasket to the thermostat. Install the thermostat with the jiggle valve upward. NOTE: The jiggle valve may be set within 10° on either side of the prescribed position.
  6. Install water inlet . Install the water inlet with 2 nuts.
  7. Add coolant (See «COOLANT (2AZ-FE)»(ref-179473-S18914038582005070800000) ) .
  8. Inspect coolant leaks (See «COOLING SYSTEM (2AZ-FE)»(ref-179473-S39267686102005070800000) ) .

Scheme 15

Scheme 15: REPLACEMENT
Scheme 15: REPLACEMENT
  1. Drain coolant . CAUTION: To avoid the danger of being burned, do not remove the radiator cap while the engine and radiator are still hot, as fluid and steam can be blown out under pressure. Remove the radiator cap. Loosen the radiator plug and drain the coolant.
  2. Add coolant Tighten the radiator drain plug, and pour coolant into radiator until it overflows. NOTE: Press the radiator inlet and outlet hose several times with hard. If the coolant level gets lower, pour coolant. Tighten the radiator cap. Pour engine coolant into the reservoir tank until it reaches full line. Warm up the engine until the thermostat valve begins to open. NOTE: Press the radiator inlet and outlet hose several times with hard during the warming up. Stop the engine and wait until the coolant temp. gets cold. Then remove the radiator cap to check the coolant level. If the level gets lower, perform the procedures above again. If the level does not gets lower, adjust the reservoir tank coolant level.
  3. Inspect coolant leaks . Fill the radiator with coolant and attach a radiator cap tester. Pump it to 118 kPa (1.2 kgf/cm 2 ), and check leakage.

Note. It is normal that the cooling fan sometime rotates when the ignition switch is turned from ACC to ON.

  1. Check cooling fan operation with low temperature (below 83°C (181°F)) . Turn the ignition switch ON. Check that the cooling fan stops. If not, check the cooling fan relay and water temperature sensor, and check for disconnection of connectors or wire break between the cooling fan relay and water temperature sensor. Disconnect the water temperature sensor connector. Check that the cooling fan rotates. If not, check the fuses, cooling fan relay, engine ECU and cooling fan, and check for a short circuit between the cooling fan relay and water temperature sensor. Reconnect the water temperature sensor connector.
  2. Check cooling fan operation with high temperature (Above 98°C (208°F)) . Start the engine, and raise coolant temperature to above 98°C (208°F). Check that the cooling fan rotates. If not, replace the water temperature sensor.
  3. Inspect cooling fan . Disconnect the cooling fan connector. Connect battery and ammeter to the cooling fan connector. Check that the cooling fan rotates smoothly, and check the reading on the ammeter. Standard amperage: 7.6 - 10.6 A at 20°C (68°F) Reconnect the cooling fan connector.

Scheme 16

Scheme 16: INSPECTION
Scheme 16: INSPECTION
  1. Cooling Fan Relay Inspect the cooling fan relay continuity. Using an ohmmeter, check that there is continuity between terminals 1 and 2. If there is no continuity, replace the relay. Check that there is no continuity between terminals 3 and 5. If there is continuity, replace the relay. Apply battery voltage across terminals 1 and 2. Using an ohmmeter, check that there is continuity between terminals 3 and 5. If there is no continuity, replace the relay.

Scheme 17

Scheme 17: INSPECTION
Scheme 17: INSPECTION
  1. Inspect water pump assy . Visually check the drain hole for coolant leakage. Turn the pulley, and check that the water pump bearing moves smoothly and quietly.

Scheme 18

Scheme 18: REPLACEMENT
Scheme 18: REPLACEMENT

Scheme 19

Scheme 19
Scheme 19
  1. Drain coolant (See «COOLANT (1MZ-FE)»(ref-179473-S08293078242005070800000) ) .
  2. Separate battery negative terminal .
  3. Remove front wheel RH .
  4. Remove front fender apron seal RH .
  5. Remove V (cooler compressor to crankshaft pulley) belt No. 1 .
  6. Remove vane pump V belt .
  7. Remove engine moving control rod. .
  8. Remove engine mounting stay No. 2 RH. .
  9. Remove generator bracket No. 2 .
  10. Remove crankshaft pulley (See «TIMING BELT»(ref-155600-S41235774502003061800000) ) . SST 09213-54015 (91651-60855), 09330-00021, 09950-50013 (09951-05010, 09952- 05010, 09953-05010, 09954-05030)
  11. Remove timing belt No. 1 cover .
  12. Remove timing belt No. 2 cover (See «TIMING BELT»(ref-155600-S41235774502003061800000) ) .
  13. Remove transverse engine mounting bracket .
  14. Remove timing belt guide No. 2 .
  15. Remove timing belt (See «ENGINE OILING»(ref-159178-S40769617142003111700000) ) .
  16. Remove timing belt idler sub-assy No. 2 . Remove the bolt and timing belt idler sub assembly No. 2.
  17. Remove camshaft timing pulley (See «CAMSHAFT»(ref-159178-S06751180662003111700000) ) . SST 09960-10010 (09962-01000, 09963-01000), 09249-63010
  18. Remove timing belt No. 3 cover .
  19. Remove water pump assy . Remove the 4 bolts, 2 nuts and water pump assembly.
  20. Install water pump assy . Install a new gasket and the water pump with the 4 bolts and 2 nuts. Torque: 8 N.m (82 kgf.cm, 71 in.lbf)
  21. Install timing belt No. 3 cover (See «CAMSHAFT»(ref-159178-S06751180662003111700000) ) .
  22. Install camshaft timing pulley (See «CAMSHAFT»(ref-159178-S06751180662003111700000) ) . SST 09962-01000, 09963-01000), 09960-10010, 09249-63010
  23. Install timing belt idler sub-assy No. 2 . Torque: 43 N.m (438 kgf.cm, 32 ft.lbf)
  24. Inspect timing belt (See «TIMING BELT REPLACEMENT»(ref-155600) ) .
  25. Install timing belt (See «TIMING BELT REPLACEMENT»(ref-155600) ) . SST 09960-10010 (09962-01000, 09963-01000)
  26. Install chain tensioner assy No. 1 (See «TIMING BELT REPLACEMENT»(ref-155600) ) .
  27. Install timing belt guide No. 2 (See «TIMING BELT REPLACEMENT»(ref-155600) ) .
  28. Install transverse engine mounting bracket . Torque: 28 N.m (286 kgf.cm, 21 ft.lbf)
  29. Install timing belt No. 2 cover (See «TIMING BELT REPLACEMENT»(ref-155600) ) .
  30. Install timing belt No. 1 cover (See «TIMING BELT REPLACEMENT»(ref-155600) ) .
  31. Install crankshaft pulley (See «TIMING BELT REPLACEMENT»(ref-155600) ) . SST 09213-54015 (91651-60855), 09330-00021
  32. Install generator bracket No. 2 . Torque: 28 N.m (286 kgf.cm, 21 ft.lbf)
  33. Install engine mounting stay No. 2 RH (See «ENGINE»(ref-159178-S20292648102003111700000) ) .
  34. Install engine moving control rod (See «ENGINE»(ref-159178-S20292648102003111700000) ) .
  35. Install vane pump V belt. .
  36. Install V (cooler compressor to crankshaft pulley) belt No. 1. .
  37. Inspect drive belt deflection and tension. .
  38. Add coolant (See «COOLANT (1MZ-FE)»(ref-179473-S08293078242005070800000) ) .
  39. Inspect coolant leaks (See «COOLANT (1MZ-FE)»(ref-179473-S08293078242005070800000) ) .
  40. Install front wheel RH . Torque: 103 N.m (1051 kgf.cm, 76 ft.lbf)

Scheme 20

Scheme 20: REPLACEMENT
Scheme 20: REPLACEMENT
  1. Drain coolant (See «COOLANT (1MZ-FE)»(ref-179473-S08293078242005070800000) )
  2. Remove battery .
  3. Remove air cleaner assy . Disconnect the MAF meter connector and wire clamp. Disconnect the VSV connector for canister closed valve (CCV) and air hose. Disconnect the 3 vacuum hoses. Loosen the hose clamp. Remove the air cleaner cap. Remove the air filter. Remove the 3 bolts and air cleaner case.
  4. Separate radiator hose outlet .
  5. Remove water inlet pipe . Remove the bolt and water inlet pipe.
  6. Remove water inlet . Remove the 3 bolts and water inlet.
  7. Remove thermostat .
  8. Install thermostat . Install a new gasket to the thermostat. Align the thermostat jiggle valve with the upper stud bolt, and insert the thermostat in the water inlet housing. NOTE: The jiggle valve may be set within 15° of either side of the prescribed position.
  9. Install water inlet . Torque: 8 N.m (82 kgf.cm, 71 in.lbf)
  10. Install water inlet pipe . Install a new O-ring to the water inlet pipe. Apply soapy water to the O-ring. Connect the water inlet pipe to the water inlet. Install the bolt holding the water inlet pipe to the cylinder head. Torque: 20 N.m (204 kgf.cm, 15 ft.lbf)
  11. Install air cleaner assy . Torque: 5 N.m (51 kgf.cm, 15 ft.lbf)
  12. Add coolant (See «COOLANT (1MZ-FE)»(ref-179473-S08293078242005070800000) )
  13. Inspect coolant leaks (See «COOLANT (1MZ-FE)»(ref-179473-S08293078242005070800000) )

Scheme 21

Scheme 21: REPLACEMENT
Scheme 21: REPLACEMENT
  1. Drain coolant . CAUTION: To avoid the danger of being burned, do not remove the radiator cap while the engine and radiator are still hot, as fluid and steam can be blown out under pressure. Remove the radiator cap. Loosen the radiator plug and drain the coolant.
  2. Add coolant . Tighten the radiator drain plug, and pour coolant into radiator until it overflows. NOTE: Press the radiator inlet and outlet hose several times with hand. If the coolant level gets lower, add coolant. Tighten the radiator cap. Pour engine coolant into the reservoir tank until it reaches full line. Warm up the engine until the thermostat valve begins to open. NOTE: Press the radiator inlet and outlet hose several times with hard during the warming up. Stop the engine and wait until the coolant temp. gets cold. Then remove the radiator cap to check the coolant level. If the level gets lower, perform the procedures above again. If the level does not gets lower, adjust the reservoir tank coolant level.
  3. Inspect coolant leaks . Fill the radiator with coolant and attach a radiator cap tester. Pump it to 118 kPa (1.2 kgf/cm 2 ), and check leakage.

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