Engine Cooling System (Service Information): Removal & Installation Lexus GS IV

INSTALLATION [03/2012 - ]

1. INSTALL WATER INLET WITH THERMOSTAT SUB-ASSEMBLY Install a new gasket and the water inlet with thermostat sub-assembly with the 3 nuts. Torque: 10 N*m (102 kgf*cm, 7 ft.*lbf)
2. CONNECT NO. 6 WATER BY-PASS HOSE Connect the No. 6 water by-pass hose to the water inlet assembly and secure it with the clip.
3. CONNECT NO. 2 RADIATOR HOSE Connect the No. 2 radiator hose to the water inlet with thermostat sub-assembly and secure it with the clip.
4. ADD ENGINE COOLANT See step 5
5. INSPECT FOR COOLANT LEAK . Refer to «ON-VEHICLE INSPECTION [03/2012 - ] - Step 1»(ref-600563-S26066385202014022400000)
6. INSTALL NO. 1 AIR CLEANER INLET . Refer to «INSTALLATION [03/2012 - ] - Step 75»(ref-600560-S18093750712014022400000)
7. INSTALL COOL AIR INTAKE DUCT SEAL . Refer to «INSTALLATION [03/2012 - ] - Step 117»(ref-600560-S18093750712014022400000)
8. INSTALL ENGINE ROOM SIDE COVER . Refer to «INSTALLATION [03/2012 - ] - Step 118»(ref-600560-S18093750712014022400000)
9. INSTALL V-BANK COVER SUB-ASSEMBLY . Refer to «INSTALLATION [03/2012 - ] - Step 116»(ref-600560-S18093750712014022400000)

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1. INSPECT COOLING FAN MOTOR Disconnect the cooling fan motor connector. Check that the motor turns smoothly when the battery is connected to the fan motor connector. TEXT IN ILLUSTRATION *a Component without harness connected (Cooling Fan Motor) Measure the current according to the value(s) in the table below. Standard Current Tester Connection Condition Specified Condition 2 (+) 20°C (68°F) 4.5 to 10.5 A If the result is not as specified, replace the cooling fan motor. Connect the cooling fan motor connector.
2. INSPECT NO. 2 COOLING FAN MOTOR Disconnect the No. 2 cooling fan motor connector. Check that the motor turns smoothly when the battery is connected to the fan motor connector. TEXT IN ILLUSTRATION *a Component without harness connected (No. 2 Cooling Fan Motor) Measure the current according to the value(s) in the table below. Standard Current Tester Connection Condition Specified Condition 2 (+) 20°C (68°F) 4.5 to 10.5 A If the result is not as specified, replace the No. 2 cooling fan motor. Connect the No. 2 cooling fan motor connector.

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1. REMOVE ENGINE ROOM SIDE COVER . Refer to «REMOVAL [03/2012 - ] - Step 1»(ref-600560-S04080038042014022400000)
2. REMOVE COOL AIR INTAKE DUCT SEAL . Refer to «REMOVAL [03/2012 - ] - Step 2»(ref-600560-S04080038042014022400000)
3. REMOVE NO. 1 AIR CLEANER INLET . Refer to «REMOVAL [03/2012 - ] - Step 29»(ref-600560-S04080038042014022400000)
4. REMOVE V-BANK COVER SUB-ASSEMBLY . Refer to «REMOVAL [03/2012 - ] - Step 3»(ref-600560-S04080038042014022400000)
5. REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE . Refer to «REMOVAL [03/2012 - ] - Step 7»(ref-600565-S03651640162014022400000)
6. DRAIN ENGINE COOLANT See step 4
7. REMOVE NO. 1 RADIATOR HOSE See step 12
8. REMOVE RADIATOR RESERVOIR TANK See step 13
9. DISCONNECT NO. 2 RADIATOR HOSE Detach the clamp and disconnect the No. 2 radiator hose from the fan shroud.
10. DISCONNECT NO. 2 ENGINE ROOM WIRE See step 17
11. DISCONNECT NO. 2 OIL COOLER OUTLET HOSE Detach the flexible hose clamp to disconnect No. 2 oil cooler outlet hose.
12. REMOVE FAN SHROUD See step 21
13. REMOVE COOLING FAN ECU Disconnect the 3 clamps and 2 connectors. Remove the 2 screws and cooling fan ECU.
14. REMOVE FAN Remove the nut and fan.
15. REMOVE NO. 2 FAN Remove the nut and No. 2 fan.
16. REMOVE COOLING FAN MOTOR Remove the 3 screws and cooling fan motor.
17. REMOVE NO. 2 COOLING FAN MOTOR Remove the 3 screws and No. 2 cooling fan motor.

1. INSTALL NO. 2 COOLING FAN MOTOR Install the No. 2 cooling fan motor with the 3 screws. Torque: 2.6 N*m (26 kgf*cm, 23 in.*lbf)
2. INSTALL COOLING FAN MOTOR Install the cooling fan motor with the 3 screws. Torque: 2.6 N*m (26 kgf*cm, 23 in.*lbf)
3. INSTALL NO. 2 FAN Install the No. 2 fan with the nut. Torque: 6.3 N*m (64 kgf*cm, 56 in.*lbf)
4. INSTALL FAN Install the fan with the nut. Torque: 6.3 N*m (64 kgf*cm, 56 in.*lbf)
5. INSTALL COOLING FAN ECU Install the cooling fan ECU with the 2 screws. Torque: 2.6 N*m (26 kgf*cm, 23 in.*lbf) Connect the 2 connectors and 3 clamps.
6. INSTALL FAN SHROUD See step 1
7. CONNECT NO. 2 OIL COOLER OUTLET HOSE Attach the flexible hose clamp to connect the No. 2 oil cooler outlet hose.
8. CONNECT NO. 2 ENGINE ROOM WIRE See step 5
9. CONNECT NO. 2 RADIATOR HOSE Attach the clamp and connect the No. 2 radiator hose to the fan shroud.
10. INSTALL RADIATOR RESERVOIR TANK See step 9
11. INSTALL NO. 1 RADIATOR HOSE See step 10
12. INSTALL AIR CLEANER CAP WITH AIR CLEANER HOSE . Refer to «INSTALLATION [03/2012 - ] - Step 2»(ref-600565-S34117039542014022400000)
13. ADD ENGINE COOLANT See step 5
14. INSPECT FOR COOLANT LEAK . Refer to «ON-VEHICLE INSPECTION [03/2012 - ] - Step 1»(ref-600563-S26066385202014022400000)
15. INSTALL NO. 1 AIR CLEANER INLET . Refer to «INSTALLATION [03/2012 - ] - Step 75»(ref-600560-S18093750712014022400000)
16. INSTALL V-BANK COVER SUB-ASSEMBLY . Refer to «INSTALLATION [03/2012 - ] - Step 116»(ref-600560-S18093750712014022400000)
17. INSTALL COOL AIR INTAKE DUCT SEAL . Refer to «INSTALLATION [03/2012 - ] - Step 117»(ref-600560-S18093750712014022400000)
18. INSTALL ENGINE ROOM SIDE COVER . Refer to «INSTALLATION [03/2012 - ] - Step 118»(ref-600560-S18093750712014022400000)

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1. INSPECT COOLING FAN ECU Put the vehicle in the following conditions: Turn the power switch off. The coolant temperature is less than 92°C (198°F). The battery voltage is between 11 and 14 V. The A/C switch is off. Clamp the 400 A probe of an ammeter over the M+ wire of each cooling fan motor. Turn the power switch on (IG) and wait for approximately 10 seconds. Check that the fan stops. Put the engine in inspection mode. Refer to «INSPECTION MODE PROCEDURE [03/2012 - ]»(ref-600412-S34816019962014022400000) . Start the engine. Check that the fan is stopped with the engine idling. HINT: Make sure that the radiator engine coolant temperature is less than 92°C (198°F). Make sure that the A/C switch is off. Check that the fan operates when the A/C switch is turned on (MAX COOL and the magnetic clutch is operating). Standard Current Item Specified Condition Cooling fan motor 1 to 6 A No. 2 cooling fan motor 1 to 6 A HINT: The coolant temperature is less than 92°C (198°F). Check that the fan operates when the engine coolant temperature sensor connector is disconnected. Standard Current Item Specified Condition Cooling fan motor 5 to 9 A No. 2 cooling fan motor 5 to 9 A After the engine is warmed up, check that the fan operates as shown in the illustration. TEXT IN ILLUSTRATION *a Operating Diagram *b A/C off *c Fan Speed *d Engine Coolant Temperature HINT: The coolant temperature at which the fan starts operating is approximately 94°C (201°F). This system can also be checked using the Techstream. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

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1. CHECK RESERVOIR TANK CAP SUB-ASSEMBLY Measure the valve opening pressure. If there are water stains or foreign matter on the O-ring, clean it with water and finger scouring. TEXT IN ILLUSTRATION *1 O-ring *2 Rubber Packing NOTE: Do not use any tools. Check that the O-ring is not deformed, cracked or damaged. Check that the O-ring is not swollen. If there are water stains or foreign matter on O-ring 1, clean it with water and finger scouring. Check that O-ring 1 is not deformed, cracked or swollen. Apply engine coolant to O-ring 1 and rubber packing 2 before using the radiator cap tester. When using the cap tester, tilt it 30° or more. TEXT IN ILLUSTRATION *1 Radiator Cap Tester *2 Reservoir Tank Cap Sub-assembly *a 30° or more Pump the cap tester several times, and check the maximum pressure*1. Pumping speed 1 pump per second HINT: *1: Even if the cap cannot maintain the maximum pressure, it is not necessarily defective. Judgment Criterion Item Specified Condition Standard value (for brand-new cap) 94 to 122 kPa (1.0 to 1.2 kgf/cm 2 , 13.6 to 17.7 psi) Minimum standard value (for used cap) 79 kPa (0.8 kgf/cm 2 , 11.4 psi) If the maximum pressure is less than the minimum standard value, replace the reservoir tank cap sub-assembly.

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1. REMOVE ENGINE ROOM SIDE COVER . Refer to «REMOVAL [03/2012 - ] - Step 1»(ref-600560-S04080038042014022400000)
2. REMOVE COOL AIR INTAKE DUCT SEAL . Refer to «REMOVAL [03/2012 - ] - Step 2»(ref-600560-S04080038042014022400000)
3. REMOVE MILLIMETER WAVE RADAR SENSOR ASSEMBLY (w/ Dynamic Radar Cruise Control System) Refer to «REMOVAL [03/2012 - ]»(ref-600437-S01407174582014022400000)
4. REMOVE V-BANK COVER SUB-ASSEMBLY . Refer to «REMOVAL [03/2012 - ] - Step 3»(ref-600560-S04080038042014022400000)
5. REMOVE NO. 1 AIR CLEANER INLET . Refer to «REMOVAL [03/2012 - ] - Step 29»(ref-600560-S04080038042014022400000)
6. REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE . Refer to «REMOVAL [03/2012 - ] - Step 7»(ref-600565-S03651640162014022400000)
7. REMOVE ENGINE UNDER COVER . Refer to «REMOVAL [03/2012 - ] - Step 21»(ref-600560-S04080038042014022400000)
8. DRAIN ENGINE COOLANT See step 4
9. REMOVE HOOD LOCK RELEASE LEVER PROTECTOR . Refer to «REMOVAL [03/2012 - ] - Step 7»(ref-600591-S24030502662014022400000)
10. DISCONNECT HOOD LOCK CONTROL CABLE ASSEMBLY Detach the clamp and disconnect the hood lock control cable.
11. REMOVE HOOD LOCK ASSEMBLY . Refer to «REMOVAL [03/2012 - ] - Step 8»(ref-600591-S24030502662014022400000)
12. REMOVE NO. 1 RADIATOR HOSE
13. REMOVE RADIATOR RESERVOIR TANK Detach the clamp, move the 2 hose clamps and remove the radiator reservoir tank hose. TEXT IN ILLUSTRATION *1 Reservoir Tank Outlet Hose *2 Radiator Reservoir Tank Hose *3 Radiator Reservoir Tank Detach the clamp, move the hose clamp and disconnect the reservoir tank outlet hose. Disconnect the wire harness clamp and remove the 2 bolts and radiator reservoir tank.
14. DISCONNECT NO. 2 RADIATOR HOSE Detach the clamp and disconnect the No. 2 radiator hose from the fan shroud. Disconnect the No. 2 radiator hose from the radiator assembly.
15. DISCONNECT NO. 2 OIL COOLER INLET HOSE Disconnect the No. 2 oil cooler inlet hose from the radiator assembly.
16. DISCONNECT NO. 2 OIL COOLER OUTLET HOSE Detach the flexible hose clamp and disconnect the No. 2 oil cooler outlet hose from the radiator assembly.
17. DISCONNECT NO. 2 ENGINE ROOM WIRE Disconnect the 6 wire harness clamps, connector and No. 2 engine room wire.
18. REMOVE UPPER RADIATOR SUPPORT Disconnect the 5 wire harness clamps and 3 connectors. Remove the 5 bolts and upper radiator support.
19. SEPARATE COOLER CONDENSER ASSEMBLY Remove the 4 bolts and separate the cooler condenser assembly from the radiator assembly.
20. REMOVE RADIATOR ASSEMBLY Remove the radiator assembly from the vehicle together with the cooling fan assembly. NOTE: Do not allow the radiator to interfere with other parts. Remove the 2 radiator support cushions and 2 lower radiator supports.
21. REMOVE FAN SHROUD Remove the 2 bolts and detach the claw on the upper part of the fan shroud. Detach the 2 claws on the lower part of the fan shroud and remove the fan shroud.

1. INSTALL FAN SHROUD Attach the 2 claws on the lower part of the fan shroud to the radiator. Attach the claw on the upper part of the fan shroud, and then install the fan shroud to the radiator with the 2 bolts. Torque: 7.1 N*m (72 kgf*cm, 63 in.*lbf)
2. INSTALL RADIATOR ASSEMBLY Install the 2 radiator support cushions and 2 lower radiator supports to the radiator assembly. Install the radiator assembly to the vehicle together with the cooling fan assembly. NOTE: Do not allow the radiator to interfere with other parts.
3. INSTALL COOLER CONDENSER ASSEMBLY Install the cooler condenser assembly to the radiator assembly with the 4 bolts. Torque: 6.0 N*m (61 kgf*cm, 53 in.*lbf)
4. INSTALL UPPER RADIATOR SUPPORT Install the upper radiator support with the 5 bolts. Torque: 8.0 N*m (82 kgf*cm, 71 in.*lbf) Connect the 5 wire harness clamps and 3 connectors.
5. CONNECT NO. 2 ENGINE ROOM WIRE Connect the 6 wire harness clamps, connector and No. 2 engine room wire.
6. CONNECT NO. 2 OIL COOLER OUTLET HOSE Connect the No. 2 oil cooler outlet hose to the radiator assembly and secure it with the hose clamp. Attach the flexible hose clamp.
7. CONNECT NO. 2 OIL COOLER INLET HOSE Connect the No. 2 oil cooler inlet hose to the radiator assembly and secure it with the hose clamp.
8. CONNECT NO. 2 RADIATOR HOSE Attach the clamp and connect the No. 2 radiator hose to the fan shroud. Connect the No. 2 radiator hose to the radiator assembly and secure it with the clamp.
9. INSTALL RADIATOR RESERVOIR TANK Install the radiator reservoir tank with the 2 bolts. Torque: 5.0 N*m (51 kgf*cm, 44 in.*lbf) Connect the wire harness clamp. Connect the reservoir tank outlet hose, secure it with the hose clamp and attach the clamp. Install the radiator reservoir tank hose, secure it with the 2 hose clamps and attach the clamp.
10. INSTALL NO. 1 RADIATOR HOSE Install the No. 1 radiator hose and secure it with the 2 clamps.
11. INSTALL HOOD LOCK ASSEMBLY . Refer to «INSTALLATION [03/2012 - ] - Step 2»(ref-600591-S14920051042014022400000)
12. CONNECT HOOD LOCK CONTROL CABLE ASSEMBLY Attach the clamp and connect the hood lock control cable.
13. INSTALL HOOD LOCK RELEASE LEVER PROTECTOR . Refer to «INSTALLATION [03/2012 - ] - Step 3»(ref-600591-S14920051042014022400000)
14. INSTALL AIR CLEANER CAP WITH AIR CLEANER HOSE . Refer to «INSTALLATION [03/2012 - ] - Step 2»(ref-600565-S34117039542014022400000)
15. ADD ENGINE COOLANT See step 5
16. INSPECT FOR COOLANT LEAK . Refer to «ON-VEHICLE INSPECTION [03/2012 - ] - Step 1»(ref-600563-S26066385202014022400000)
17. INSTALL NO. 1 AIR CLEANER INLET . Refer to «INSTALLATION [03/2012 - ] - Step 75»(ref-600560-S18093750712014022400000)
18. INSTALL ENGINE UNDER COVER . Refer to «INSTALLATION [03/2012 - ] - Step 115»(ref-600560-S18093750712014022400000)
19. INSTALL V-BANK COVER SUB-ASSEMBLY . Refer to «INSTALLATION [03/2012 - ] - Step 116»(ref-600560-S18093750712014022400000)
20. INSTALL MILLIMETER WAVE RADAR SENSOR ASSEMBLY (w/ Dynamic Radar Cruise Control System) Refer to «INSTALLATION [03/2012 - ]»(ref-600437-S20792630242014022400000)
21. ADJUST MILLIMETER WAVE RADAR SENSOR ASSEMBLY (w/ Dynamic Radar Cruise Control System) . Refer to «ADJUSTMENT [03/2012 - ] - Step 1»(ref-600437-S08511103972014022400000)
22. INSTALL COOL AIR INTAKE DUCT SEAL . Refer to «INSTALLATION [03/2012 - ] - Step 117»(ref-600560-S18093750712014022400000)
23. INSTALL ENGINE ROOM SIDE COVER . Refer to «INSTALLATION [03/2012 - ] - Step 118»(ref-600560-S18093750712014022400000)

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1. INSPECT COOLING FAN RELAY (FAN NO. 1) Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 3 - 5 Battery voltage is not applied between terminals 1 and 2 10 kohms or higher 3 - 5 Battery voltage is applied between terminals 1 and 2 Below 1 ohms If the result is not as specified, replace the cooling fan relay.