Engine Cooling System: Other Chevrolet Sonic I

Temperature Versus Resistance

Temperature Versus Resistance

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

COMPONENT CONNECTOR END VIEWS - INDEX

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.
2. Verify the scan tool Radiator Coolant Temperature Sensor parameter is between -39 to + 120°C (-38 to +248°F) and changes with engine run time. If not between -39 to + 120°C (-38 to +248°F) or does not change Refer to «Circuit/System Testing»(ref-542500-S07022616462013041600000) . If between -39 to + 120°C (-38 to +248°F) and changes
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
4. Verify the DTC does not set. If the DTC sets Refer to «Circuit/System Testing»(ref-542500-S07022616462013041600000) . If the DTC does not set
5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Engine Coolant Temperature Sensor Replacement (Water Outlet)»(ref-542528-S14456952412013041600000) , «Engine Coolant Temperature Sensor Replacement (Thermostat)»(ref-542528-S03996121602013041600000) , «Engine Coolant Temperature Sensor Replacement (Radiator)»(ref-542528-S42457888152013041600000) for radiator coolant temperature sensor replacement.
2. «Engine Control Module Replacement»(ref-542510-S11643045202013041600000) for engine control module replacement, setup, and programming.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

COMPONENT CONNECTOR END VIEWS - INDEX

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Engine running, observe the DTC information with a scan tool. DTC P00B3, P00B4, P0117, P0118, P0597, P0598, or P0599 should not be set. If a DTC is set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-542476-S32003136202013041600000) for further diagnosis.
2. Verify the coolant in the radiator surge tank is at the correct level and there are no engine coolant leaks. Refer to «Cooling System Draining and Filling»(ref-542500-S12642615042013041600000) , and «Loss of Coolant»(ref-542500-S42302016122013041600000) .
3. Engine idling for 15 minutes with the A/C OFF.
4. Command the engine coolant thermostat heater to 100 percent with a scan tool. Increase the engine speed to 3,000 RPM. Observe the scan tool radiator coolant temperature sensor and ECT sensor parameters. The radiator coolant temperature sensor and the ECT sensor parameters should be within 20°C (68°F).
5. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Engine Coolant Temperature Sensor Replacement (Water Outlet)»(ref-542528-S14456952412013041600000) , «Engine Coolant Temperature Sensor Replacement (Thermostat)»(ref-542528-S03996121602013041600000) , «Engine Coolant Temperature Sensor Replacement (Radiator)»(ref-542528-S42457888152013041600000)
2. «Engine Control Module Replacement»(ref-542510-S11643045202013041600000) for ECM replacement, setup, and programming

Schematic Reference

Engine Controls Schematics

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Engine Running, observe the DTC information with a scan tool. DTC P00B3, P00B4, P00B6, P0117, P0118, P0597, P0598, and P0599 should not be set. If a DTC is set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-542476-S32003136202013041600000) for further diagnosis.
2. Verify the coolant in the radiator surge tank is at the correct level and there are no engine coolant leaks. Refer to «Cooling System Draining and Filling»(ref-542500-S12642615042013041600000) , and «Loss of Coolant»(ref-542500-S42302016122013041600000) .
3. Verify the engine cooling fan operates. Refer to «Cooling Fan Inoperative (LUV)»(ref-542500-S19440832022013041600000) , «Cooling Fan Inoperative (LUW, LWE)»(ref-542500-S12084670822013041600000) .
4. Engine idling for 15 minutes with the A/C OFF.
5. Command the Engine Coolant Thermostat Heater to 100 percent with a scan tool. Increase the engine speed to 3,000 RPM. Observe the scan tool ECT sensor parameter. The temperature should decrease to less than 85°C (185°F).
6. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Engine Coolant Thermostat Replacement (LUV) , Engine Coolant Thermostat Replacement (LUW)

Schematic Reference

Engine Heating/Cooling Schematics

Connector End View Reference

1. «COMPONENT CONNECTOR END VIEWS - INDEX»(ref-543151-S39696903712013042200000)
2. «Electrical Center Identification Views»(ref-542536-S24629493602013041600000)

Description and Operation

Cooling Fan Description and Operation (LUV) , Cooling Fan Description and Operation (LWE, LUW)

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON.
2. Verify an audible click is heard or felt from each cooling fan relay when commanding the cooling fan ON and OFF with a scan tool. If a click is not heard or felt at each of the relays Refer to «Circuit/System Testing»(ref-542500-S00155024532013041600000) . If a click is heard or felt at each of the relays
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
4. Verify the DTC does not set. If the DTC sets Refer to «Circuit/System Testing»(ref-542500-S00155024532013041600000) . If the DTC does not set
5. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Relay Replacement (Within an Electrical Center)»(ref-542513-S01448277202013041600000) , «Relay Replacement (Attached to Wire Harness)»(ref-542513-S06096887402013041600000)
2. «Control Module References»(ref-542499-S01936129122013041600000) for ECM replacement, programming, and setup

Schematic Reference

Engine Heating/Cooling Schematics

Connector End View Reference

1. «COMPONENT CONNECTOR END VIEWS - INDEX»(ref-543151-S39696903712013042200000)
2. «Electrical Center Identification Views»(ref-542536-S24629493602013041600000)

Description and Operation

Cooling Fan Description and Operation (LUV) , Cooling Fan Description and Operation (LWE, LUW)

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON.
2. Verify an audible click is heard or felt from each cooling fan relay when commanding the cooling fan ON and OFF with a scan tool. If a click is not heard or felt at each of the relays Refer to «Circuit/System Testing»(ref-542500-S37062686162013041600000) . If a click is heard or felt at each of the relays
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
4. Verify the DTC does not set. If the DTC sets Refer to «Circuit/System Testing»(ref-542500-S37062686162013041600000) . If the DTC does not set
5. All OK.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Relay Replacement (Within an Electrical Center)»(ref-542513-S01448277202013041600000) , «Relay Replacement (Attached to Wire Harness)»(ref-542513-S06096887402013041600000)
2. «Control Module References»(ref-542499-S01936129122013041600000) for ECM replacement, setup, and programming

Schematic Reference

Engine Controls Schematics

Connector End View Reference

COMPONENT CONNECTOR END VIEWS - INDEX

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Verify the coolant in the radiator surge tank is at the correct level and there are no engine coolant leaks. «Loss of Coolant»(ref-542500-S42302016122013041600000) , and «Cooling System Draining and Filling»(ref-542500-S12642615042013041600000) If the coolant level is not correct Repair as necessary. If the coolant level is correct
2. Ignition ON.
3. Verify the parameters listed below do not display Malfunction when commanding the Engine Coolant Thermostat Heater ON and OFF with a scan tool. Engine Coolant Thermostat Heater Control Circuit Low Voltage Test Status Engine Coolant Thermostat Heater Control Circuit Open Test Status Engine Coolant Thermostat Heater Control Circuit High Voltage Test Status If Malfunction is displayed Refer to «Circuit/System Testing»(ref-542500-S36479040872013041600000) . If Malfunction is not displayed
4. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
5. Verify the DTC does not set. If any DTC sets Refer to «Circuit/System Testing»(ref-542500-S36479040872013041600000) . If the DTC does not set
6. All OK.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Engine Coolant Thermostat Replacement (LUV)»(ref-542500-S38357674202013041600000) , «Engine Coolant Thermostat Replacement (LUW)»(ref-542500-S06740968532013041600000) for E41 engine coolant thermostat heater replacement.
2. «Control Module References»(ref-542499-S01936129122013041600000) for engine control module, replacement, programming, and setup.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

Cooling System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

Scan Tool Reference

Control Module References for scan tool information

1. Engine running, observe the DTC information with a scan tool. DTC P00B3, P00B4, P00B6, P0117, or P0118 should not be set. If a DTC is set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-542476-S32003136202013041600000) for further diagnosis.
2. Verify the coolant in the radiator surge tank is at the correct level and there are no engine coolant leaks. Refer to «Cooling System Draining and Filling»(ref-542500-S12642615042013041600000) , and «Loss of Coolant»(ref-542500-S42302016122013041600000) .
3. Engine idling for 15 min with the A/C OFF. Verify the engine cooling fan is not ON at all times.
4. Command the Engine Coolant Thermostat Heater to 0 % with a scan tool. Increase the engine speed to 3,000 RPM. Observe the scan tool ECT sensor parameter. The temperature should increase to greater than 102°C (215°F). If less than the specified value, replace the E41 engine coolant thermostat heater.
5. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Engine Coolant Thermostat Replacement (LUV) , Engine Coolant Thermostat Replacement (LUW)

Identifying Intermittent Conditions

Many intermittent conditions occur with harness or connector movement due to engine torque, rough pavement, vibration or physical movement of a component. Refer to the following for a list to help isolate an intermittent condition

1. Water intrusion in connectors, terminals, or components
2. Poor connector mating
3. Terminal contact
4. High circuit or component resistance-High resistance can include any resistance, regardless of the amount, which can interrupt the operation of the component.
5. Harness' that are routed too tight, or chaffed circuits
6. High or low ambient temperatures
7. High or low engine coolant temperatures
8. High underhood temperatures
9. Heat build up in components or circuits due to circuit resistance, poor terminal contact, or high electrical load
10. High or low system voltage
11. High vehicle load conditions
12. Rough road surface
13. Electro-magnetic interference (EMI)/circuit interference from relays, solenoids or other electrical surge
14. Incorrect installation of non-factory, aftermarket, or after factory add on accessories

If an intermittent is detected, refer to Testing for Intermittent Conditions and Poor Connections for specific strategies in diagnosing intermittent conditions.

Schematic Reference

Engine Heating/Cooling Schematics

Connector End View Reference

1. «COMPONENT CONNECTOR END VIEWS - INDEX»(ref-543151-S39696903712013042200000)
2. «Electrical Center Identification Views»(ref-542536-S24629493602013041600000)

Description and Operation

Cooling Fan Description and Operation (LUV) , Cooling Fan Description and Operation (LWE, LUW)

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON.
2. Verify that there are no cooling system DTCs set. If any DTCs are set Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(ref-542476-S32003136202013041600000) . If no DTCs are set
3. Verify the scan tool parameters listed below display OFF. Cooling Fan Relay 1 Command Cooling Fan Relays 2 and 3 Command If a scan tool parameter displays ON Refer to Diagnostic Aids and «Symptoms - Engine Cooling»(ref-542500-S38701010902013041600000) for further diagnosis. If both scan tool parameters display OFF
4. Verify that the fan is not activated. If the fan is operating Refer to «Circuit/System Testing»(ref-542500-S12615140692013041600000) . If the fan is OFF
5. All OK.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Relay Replacement (Within an Electrical Center) , Relay Replacement (Attached to Wire Harness)

Schematic Reference

Engine Heating/Cooling Schematics

Connector End View Reference

1. «COMPONENT CONNECTOR END VIEWS - INDEX»(ref-543151-S39696903712013042200000)
2. «Electrical Center Identification Views»(ref-542536-S24629493602013041600000)

Description and Operation

Cooling Fan Description and Operation (LUV) , Cooling Fan Description and Operation (LWE, LUW)

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON.
2. Verify that DTC P0480, P0481, P0691, P0692, P0693, or P0694 is not set. If any of the DTCs are set Refer to «DTC P0480, P0481, P0691, P0692, P0693, or P0694 (LUW, LWE)»(ref-542500-S30727483962013041600000) , «DTC P0480, P0481, P0691, P0692, P0693, or P0694 (LUV)»(ref-542500-S36483638822013041600000) . If none of the DTCs are set
3. Verify the scan tool parameters listed below display OFF: Cooling Fan Relay 1 Command Cooling Fan Relays 2 Command If a scan tool parameter displays ON Refer to Diagnostic Aids and «Symptoms - Engine Cooling»(ref-542500-S38701010902013041600000) for further diagnosis. If both scan tool parameters display OFF
4. Verify that the fan is not activated. If a fan is operating Refer to «Circuit/System Testing»(ref-542500-S26260925882013041600000) . If the fan is OFF
5. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Relay Replacement (Within an Electrical Center) , Relay Replacement (Attached to Wire Harness)

Schematic Reference

Engine Heating/Cooling Schematics

Connector End View Reference

1. «COMPONENT CONNECTOR END VIEWS - INDEX»(ref-543151-S39696903712013042200000)
2. «Electrical Center Identification Views»(ref-542536-S24629493602013041600000)

Description and Operation

Cooling Fan Description and Operation (LUV) , Cooling Fan Description and Operation (LWE, LUW)

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON.
2. Verify that DTC P0480, P0481, P0691, P0692, P0693, or P0694 is not set. If a DTC is set Refer to «DTC P0480, P0481, P0691, P0692, P0693, or P0694 (LUW, LWE)»(ref-542500-S30727483962013041600000) , «DTC P0480, P0481, P0691, P0692, P0693, or P0694 (LUV)»(ref-542500-S36483638822013041600000) . If no DTC is set
3. Verify that the G10 Cooling Fan Motor operates at low, medium, and high speed, when commanding the appropriate cooling fan relays ON and OFF with a scan tool. If the cooling fan does not operate at all speeds Refer to «Circuit/System Testing»(ref-542500-S32942201372013041600000) . If the cooling fan operates at all speeds
4. All OK.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Relay Replacement (Within an Electrical Center)»(ref-542513-S01448277202013041600000) , «Relay Replacement (Attached to Wire Harness)»(ref-542513-S06096887402013041600000)
2. «Front Compartment Fuse Block Replacement»(ref-542513-S26068647062013041600000)
3. «Engine Coolant Fan Replacement (LDE/LUW)»(ref-542500-S11405939992013041600000) , «Engine Coolant Fan Replacement (LUV)»(ref-542500-S42593348372013041600000)

Schematic Reference

Engine Heating/Cooling Schematics

Connector End View Reference

1. «COMPONENT CONNECTOR END VIEWS - INDEX»(ref-543151-S39696903712013042200000)
2. «Electrical Center Identification Views»(ref-542536-S24629493602013041600000)

Description and Operation

Cooling Fan Description and Operation (LUV) , Cooling Fan Description and Operation (LWE, LUW)

Electrical Information Reference

1. «Circuit Testing»(ref-542498-S42729642072013041600000)
2. «Connector Repairs»(ref-542498-S10348064002013041600000)
3. «Testing for Intermittent Conditions and Poor Connections»(ref-542498-S27468711012013041600000)
4. «Wiring Repairs»(ref-542498-S06256207262013041600000)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON.
2. Verify that DTC P0480, P0481, P0691, P0692, P0693, or P0694 is not set. If a DTC is set Refer to «DTC P0480, P0481, P0691, P0692, P0693, or P0694 (LUW, LWE)»(ref-542500-S30727483962013041600000) , «DTC P0480, P0481, P0691, P0692, P0693, or P0694 (LUV)»(ref-542500-S36483638822013041600000) . If no DTC is set
3. Verify that the cooling fan operates at low, medium, and high speed, when commanding the appropriate cooling fan relays ON and OFF with a scan tool. If the cooling fan does not operate at all speeds Refer to «Circuit/System Testing»(ref-542500-S19995431032013041600000) . If the cooling fan operates at all speeds
4. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Relay Replacement (Within an Electrical Center)»(ref-542513-S01448277202013041600000) , «Relay Replacement (Attached to Wire Harness)»(ref-542513-S06096887402013041600000)
2. «Engine Coolant Fan Replacement (LDE/LUW)»(ref-542500-S11405939992013041600000) , «Engine Coolant Fan Replacement (LUV)»(ref-542500-S42593348372013041600000)

Engine Overheating

Engine Overheating

Loss of Coolant

Loss of Coolant

Engine Fails To Reach Normal Operating Temperature

Engine Fails To Reach Normal Operating Temperature

Filling Procedure

1. Raise and support the vehicle.
2. Tighten the radiator drain cock (1) to 2 N.m (18 lb in).
3. Install the front compartment front insulator cover. Refer to «Front Compartment Front Insulator Cover Replacement»(ref-542501-S04169640362013041600000) .
4. Lower the vehicle.
5. Slowly fill the radiator with a 50/50 coolant mixture until the coolant level reaches the base of the radiator surge tank. Refer to «Approximate Fluid Capacities»(ref-542472-S00192311022013041600000) .
6. Allow 30 seconds for the coolant level to stabilize and continue to fill the coolant filler neck until the level stabilizes for at least 2 minutes.
7. Start the engine and allow to the engine to idle in PARK or NEUTRAL with the parking brake engaged.
8. Slowly fill the coolant mixture until the level stabilizes at the base of the radiator surge tank.
9. Install the coolant pressure cap.
10. Raise the engine RPM to 2500 rpm for 30-40 seconds.
11. Shut the engine OFF.
12. Allow the engine to cool, remove coolant fill cap and repeat steps 4-10 until the coolant level has completely stabilized within the radiator surge tank.
13. Inspect and if necessary, fill the coolant reservoir bottle as necessary.
14. Rinse away any excess coolant from the engine and the engine compartment.
15. Inspect the cooling system for leaks.
16. Top off the radiator surge tank if necessary.

Radiator Cleaning

Note. Blow compressed air through the engine side of the radiator to remove any foreign material, such as insects, leaves, and dust.

1. Warm water and mild soap may be needed in some conditions.
2. Wash the A/C condenser fin.
3. Wash the A/C condenser and radiator thoroughly.
4. Wash the radiator cooling fin.
5. Repair any damaged cooling fin.

Scheme 22

Radiator Surge Tank Replacement

Scheme 23

Radiator Surge Tank Outlet Hose Replacement (LUV)

Scheme 24

Radiator Surge Tank Outlet Hose Replacement (LDE LUW)

Scheme 25

Radiator Inlet Hose Replacement (LUV)

Repair Procedure

1. Pressure test the cooling system. Refer to «Cooling System Leak Testing»(ref-542500-S01357998282013041600000) .
2. Grind the fracture surface (1) with a proper tool.
3. Drill a hole in the center of the fractured surface, using a 6 mm (0.24 in) drill.
4. Install the new radiator mounting pin (2). Install the nut (3). NOTE: The bolt should not be longer than 35 mm (1.38 in). Install the radiator mounting pin (2) with the bolt (1).
5. Tighten the bolt 5 N.m (44 lb in).

Scheme 26

Radiator Upper Bracket Replacement

Scheme 27

Engine Coolant Fan Resistor Mount Repair

Scheme 28

Throttle Body Heater Inlet Hose Replacement (LUW)

Scheme 29

Throttle Body Heater Inlet Pipe Replacement (LUW)

Scheme 30

Throttle Body Heater Outlet Pipe Replacement (LUW)

Scheme 31

Throttle Body Heater Outlet Hose Replacement (LUW)

Water Pump

The belt-driven centrifugal water pump consists of an impeller, a drive shaft, and a belt pulley. The water pump is mounted on the front of the transverse-mounted engine and is driven by the accessory belt.

The impeller is supported by a completely sealed bearing. The water pump is serviced as an assembly and cannot be disassembled.

Thermostat

A wax pellet-type thermostat controls the flow of the engine coolant through the engine cooling system. The thermostat is mounted in the thermostat housing to the rear of the cylinder head. The thermostat stops the flow of the engine coolant from the engine to the radiator to provide faster warm-up, and to regulate the coolant temperature. The thermostat remains closed while the engine coolant is cold, preventing circulation of the engine coolant through the radiator.

As the engine warms, the thermostat opens. This allows the engine coolant to flow through the radiator where the heat is dissipated through the radiator. This opening and closing of the thermostat permits enough engine coolant to enter the radiator to keep the engine within proper engine temperature operating limits.

The wax pellet in the thermostat is hermetically sealed in a metal case. The wax element of the thermostat expands when it is heated and contracts when it is cooled.

As the vehicle is driven and the engine warms, the engine coolant temperature increases. When the engine coolant reaches a specified temperature, the wax pellet element in the thermostat expands and exerts pressure against the metal case, forcing the valve open. This allows the engine coolant to flow through the engine cooling system and cool the engine. As the wax pellet cools, the contraction allows a spring to close the valve. To provide fuel economy and low emission benefit during part load driving condition, the electric controlled thermostat enables changing the thermostat opening temperature. Basically, the thermostat begins to open at 105° C (221° F) and is fully open at 120° C (248° F) when the electric energy not assisted.

If a certain driving environment encountered that requiring better cooling performance, the ECM orders to put electric energy to the thermostat. The energized electric heater in the wax pellet gives thermal energy to the wax for assisting the wax expansion. Then the thermostat valve opens earlier than the specified coolant temperature. For this vehicle, the programmed temperature set value by the ECM is 105° C (221° F) for cold and part load driving mode and 90° C (194° F) for hot and full load driving mode.

Radiator

The radiator is a heat exchanger. It consists of a core and 2 tanks. The aluminum core is a tube and fin cross-flow design that extends from the inlet tank to the outlet tank. Fins are placed around the outside of the tubes to improve heat transfer to the atmosphere.

The inlet and outlet tanks are a molded, high temperature, nylon reinforced plastic material. A high temperature rubber gasket seals the tank flange edge to the aluminum core. The tanks are clamped to the core with clinch tabs. The tabs are part of the aluminum header at each end of the core.

The radiator removes heat from the coolant passing through it. The fins on the core transfer heat from the coolant passing through the tubes. As air passes between the fins, it absorbs heat and cools the coolant.

Surge Tank

The surge tank is a plastic tank with a threaded pressure cap. The tank is mounted at a point higher than all other coolant passages. The surge tank provides an air space in the cooling system that allows the coolant to expand and contract. The surge tank provides a coolant fill point and a central air bleed location. During vehicle use, the coolant heats and expands. The increased coolant volume flows into the surge tank. As the coolant circulates, any air is allowed to bubble out. Coolant without air bubbles absorbs heat much better than coolant with bubbles.