Scheme 1
| 1 - RETURN TUBE | 9 - SECONDARY THERMOSTAT |
|---|---|
| 2 - UPPER PLENUM | 10 - CYLINDER BLOCK |
| 3 - HEATER CORE | 11 -TRANSMISSION OIL COOLER |
| 4 - LOWER PLENUM | 12 - UPPER RADIATOR HOSE |
| 5 - PRIMARY THERMOSTAT | 13 - WATER PUMP |
| 6 - LOWER RADIATOR HOSE | 14 - CYLINDER HEAD |
| 7 - ENGINE OIL COOLER | 15 - COOLING FANS |
| 8 - PRIMARY THERMOSTAT BYPASS | 16 - RADIATOR |
The cooling system regulates engine operating temperature. It allows the engine to reach normal operating temperature as quickly as possible, maintains normal operating temperature and prevents overheating.
Scheme 2
| 1-COOLANT EXPANSION TANK | 8-UPPER TIMING CHAIN COVER |
|---|---|
| 2-ACCESSORY CARRIER BRACKET | 9-ENGINE BLOCK |
| 3-EGR COOLER | 10-WATER PUMP |
| 4-HEAT EXCHANGER/HEATER CORE | 11-TEMPERATURE SENSOR |
| 5-EGR BYPASS HOUSING | 12-THERMOSTAT HEATING ELEMENT |
| 6-EGR ACTUATOR | 13-RADIATOR |
| 7-OIL/WATER COOLER |
The cooling system also provides a means of heating the passenger compartment. The cooling system is pressurized and uses a centrifugal water pump to circulate coolant throughout the system. Gas engines use a separate and remotely mounted, ambient pressure coolant recovery bottle using a pressure/vent cap. Diesel engine use a separate and remotely mounted, pressurized coolant tank using a pressure/vent cap.
The cooling system consists
- Radiator
- Coolant
- Electric Cooling Fan
- Water pump
- Dual Thermostats (Gas Engines)
- Charge air cooler (Turbocharged vehicles only)
- Hoses and clamps
- Transmission oil cooler
- Coolant Recovery system
DESCRIPTION
| 1 - RETURN TUBE | 9 - SECONDARY THERMOSTAT |
|---|---|
| 2 - UPPER PLENUM | 10 - CYLINDER BLOCK |
| 3 - HEATER CORE | 11 -TRANSMISSION OIL COOLER |
| 4 - LOWER PLENUM | 12 - UPPER RADIATOR HOSE |
| 5 - PRIMARY THERMOSTAT | 13 - WATER PUMP |
| 6 - LOWER RADIATOR HOSE | 14 - CYLINDER HEAD |
| 7 - ENGINE OIL COOLER | 15 - COOLING FANS |
| 8 - PRIMARY THERMOSTAT BYPASS | 16 - RADIATOR |
The cooling system regulates engine operating temperature. It allows the engine to reach normal operating temperature as quickly as possible, maintains normal operating temperature and prevents overheating.
Scheme 3
| 1 - RETURN TUBE - GAS ENGINES | 10 - AFTER RUN PUMP |
|---|---|
| 2 - THERMOSTAT | 11 - CYLINDER BLOCK |
| 3 - HEATER CORE | 12 - OIL COOLER |
| 4 - UPPER PLENUM | 13 - COOLING FANS |
| 5 - LOWER PLENUM | 14 - RADIATOR |
| 6 - THERMOSTAT HOUSING | 15 - UPPER RADIATOR |
| 7 - LOWER RADIATOR HOSE | 16 - COOLING FANS |
| 8 - TURBOCHARGER | 17 - CYLINDER HEAD |
| 9 - ORIFICE PLATE |
The cooling system also provides a means of heating the passenger compartment. The cooling system is pressurized and uses a centrifugal water pump to circulate coolant throughout the system. Gas engines use a separate and remotely mounted, ambient pressure coolant recovery bottle using a pressure/vent cap. Diesel engine use a separate and remotely mounted, pressurized coolant tank using a pressure/vent cap.
The cooling system consists
- Radiator
- Coolant
- Electric Cooling Fan
- Water pump
- Dual Thermostat (Gas Engines)
- Charge air cooler (Turbocharged vehicles only)
- Hoses and clamps
- Transmission oil cooler
- Coolant Recovery system
The automatic belt tensioner maintains proper tension on the accessory drive belt. The tensioner pulley can be serviced separately.
Scheme 4
| 1 - RIGHT MOUNT BOLT ACCESS PLUG |
|---|
| 2 - FASCIA |
| 3 - SPLASH SHIELD |
| 4 - CRANKSHAFT BOLT ACCESS PLUG |
- Raise vehicle on hoist.
- Remove belt splash shield (3). 1 - POWER STEERING PUMP 2 - ACCESSORY DRIVE BELT 3 - GENERATOR 4 - CRANKSHAFT PULLEY 5 - LOWER IDLER PULLEY 6 - CRANKSHAFT PULLEY 7 - WATER PUMP PULLEY 8 - ACCESSORY DRIVE BELT TENSIONER 9 - UPPER IDLER PULLEY
- Remove accessory drive belt. Refer to «BELT, Serpentine, Removal»(ref-463907-S04169480002012041600000) .
- Remove accessory drive belt tensioner mounting bolt. Remove accessory drive belt tensioner (8).
Scheme 5
- Remove the accessory drive belt. Refer to «BELT, Serpentine, Removal»(ref-463907-S04169480002012041600000) .
- Lower the vehicle.
- Remove the tensioner bracket mounting bolts (1, 2 3).
- Raise and support the vehicle.
- Remove the tensioner assembly (4) from underneath the vehicle.
- If idler pulley is to be replaced, remove pulley from tensioner (4).
Scheme 6
- Disconnect the negative battery cable.
- Remove the water/power steering/vacuum pump assembly. Refer to «PUMP, Water, Removal»(ref-463907-S26682395342012041600000) or «PUMP, Water, Afterrun, Removal»(ref-463907-S41514956892012041600000) .
- Lower the vehicle.
- Remove the coolant recovery bottle. Refer to «BOTTLE, Coolant Recovery, Removal»(ref-463907-S06743019462012041600000) .
- Remove the charge air cooler.
- Remove the A/C condenser. Refer to «CONDENSER, A/C, Removal»(ref-463903-S11301123012012041600000) .
- Remove the A/C compressor. Refer to «COMPRESSOR, A/C, Removal»(ref-463903-S22185908492012041600000) .
- Remove the generator. Refer to «GENERATOR, Removal»(ref-463919-S02823497502012041600000) .
- Remove the EGR cooler. Refer to «COOLER, EGR, Removal»(ref-463907-S28487144482012041600000) .
- Remove the accessory drive belt tensioner. Refer to «TENSIONER, Belt, Removal»(ref-463907-S16667988902012041600000) .
- Remove the coolant bypass hose from the thermostat housing (2).
- Remove the radiator hose (3) from the thermostat housing (2).
- Remove the thermostat housing mounting bolts.
- Remove the accessory drive bracket mounting bolts.
- Remove the accessory drive bracket (1).
- If necessary, separate the thermostat (2) from the accessory drive bracket (1).
The EGR cooler cools recirculated exhaust gasses to reduce combustion temperature which results in less NOx gases.
Scheme 7
Scheme 8
Scheme 9
Scheme 10
- Disconnect the negative battery cable.
- Remove engine cover.
- Drain cooling system. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Disconnect coolant hoses (1) from the EGR cooler (2).
- Remove the upper EGR cooler bolt (1) and bracket (2).
- Remove the A/C wiring connector bracket and position aside.
- Remove the lower EGR cooler bolt (1). NOTE: Two bolts hidden under cooler.
- Remove six bolts (1) and the EGR cooler (2).
Scheme 11
- Clean all gasket mating surfaces.
- Install a new gasket (1) onto the EGR body (2).
- Install EGR cooler. Tighten bolts (1) to 9 N.m (80 in. lbs.).
- Install the lower EGR cooler bolt (1). Tighten to 9 N.m (80 in. lbs.).
- Install the A/C connector mounting bracket.
- Install the upper EGR cooler bolt. Tighten bolt to 9 N.m (80 in. lbs.).
- Connect coolant hoses (1) to the EGR cooler (2).
- Fill cooling system. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Install engine cover.
- Connect the negative battery cable.
Scheme 12
| 1 - RADIATOR TANK |
|---|
| 2 - DRAINCOCK |
| CAUTION | Use of pliers on draincock is not recommended. Damage may occur to radiator or draincock. |
Note. It is not necessary to remove draincock during a routine coolant drain.
- Remove the front passenger side wheel
- Remove the front passenger side splash shield assembly from the wheelhouse. Refer to «SHIELD, Splash, Front Wheel House, Removal»(ref-463905-S27292492672012041600000)
- Drain the cooling system. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Open the draincock (2) by turning it counterclockwise until it stops.
- Turn the draincock (2) back (clockwise) 1/8 turn.
- Pull the draincock (2) from the radiator tank (1).
The radiator cooling fans are dual-speed electric motor driven fans. The radiator fan assembly includes two electric motors, two five blade fans, and a support shroud that is attached to the radiator. The radiator fans are serviced as an assembly.
The radiator is a cross-flow type (horizontal tubes) with design features that provide greater strength, as well as sufficient heat transfer capabilities to keep the engine coolant within operating temperatures.
The radiator has an aluminum core with plastic tanks. Although stronger than brass, plastic tanks are subject to damage by impact. Always handle radiator with care.
OPERATION
The radiator functions as a heat exchanger, using air flow across the exterior of the radiator tubes. This heat is then transferred from the coolant and into the passing air.
Scheme 13
| 1 - UPPER RADIATOR CLOSURE PANEL |
|---|
| 2 - COOLING MODULE |
| 3 - RADIATOR FAN CONNECTOR |
| 4 - LOWER RADIATOR CROSSMEMBER |
| WARNING | Do not open the radiator draincock with the system hot and under pressure because serious burns from coolant can occur. |
- Drain cooling system. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Remove radiator fan. Refer to «FAN, Cooling, Removal»(ref-463907-S14236962252012041600000) .
- Disconnect lower radiator hose.
- Remove fasteners attaching AC condenser to radiator. Reposition AC condenser.
- Remove radiator assembly by lifting it up from the engine compartment. Care should be taken not to damage the cooling fins and tubes during removal.
Scheme 14
| 1 - UPPER RADIATOR CROSSMEMBER |
|---|
| 2 - COOLING MODULE |
| 3 - RADIATOR FAN CONNECTOR |
| 4 - LOWER RADIATOR CROSSMEMBER |
| WARNING | Do not open the radiator draincock with the system hot and under pressure because serious burns from coolant can occur. |
Note. It is not necessary to discharge the air conditioning system to remove the radiator.
- Disconnect negative battery cable.
- Remove engine cover. Refer to «Removal»(ref-463897-S31796280152012041600000) or «Removal»(ref-463898-S23648269112012041600000) or «Removal»(ref-463899-S40002501852012041600000) .
- Remove air cleaner housing assembly. Refer to «BODY, Air Cleaner, Removal»(ref-463897-S39248803232012041600000) or «BODY, Air Cleaner, Removal»(ref-463898-S09866072732012041600000) or «BODY, Air Cleaner, Removal»(ref-463899-S08239213792012041600000) .
- Raise vehicle on hoist.
- Drain cooling system. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Disconnect radiator fan motor electrical connector.
- Disconnect lower radiator hose.
- Remove two lower fasteners attaching radiator fan shroud to radiator.
- Disconnect Charger Air Cooler hoses from Charge Air Cooler.
- Disconnect Charger Air Cooler from radiator.
- Lower vehicle.
- Remove grille.
- Remove upper radiator hose from the radiator.
- Remove remaining fasteners attaching radiator fan shroud to radiator.
- Remove radiator fan/shroud assembly.
- Remove remaining fasteners attaching AC condenser to radiator. Reposition AC condenser.
- Unclip Charge Air Cooler from radiator remove radiator assembly by lifting it up from the engine compartment. Care should be taken not to damage the cooling fins and tubes during removal.
The sensor is located at the top of the coolant adapter housing. The ECT Sensor is a negative thermal coefficient sensor.
The ECT sensor provides an input to the PCM. As temperature increases, resistance of the sensor decreases. As coolant temperature varies, the ECT sensor resistance changes resulting in a different voltage value at the PCM ECT sensor signal circuit. The ECT sensor provides input for various PCM operations. The PCM uses the input to control air-fuel mixture, timing, and radiator fan on/off times.
Scheme 15
| 1 - ETC |
|---|
| 2 - COOLANT ADAPTER |
- Disconnect negative battery cable.
- Partially drain cooling system below level of ECT Sensor (1). Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Disconnect ECT Sensor electrical connector.
- Remove ECT Sensor (1) By pressing the locking tab down and turning the sensor counterclockwise.
Scheme 16
| 1 - FUEL RAIL |
|---|
| 2 - EGR VALVE |
| 3 - POWER STEERING PUMP |
| 4 - GENERATOR |
| 5 - COOLANT TEMPERATURE SENSOR |
| 6 - THERMOSTAT HOUSING |
| 7 - FUEL RAIL PRESSURE SENSOR |
- Disconnect negative battery cable.
- Remove engine cover. Refer to «Removal»(ref-463897-S31796280152012041600000) or «Removal»(ref-463898-S23648269112012041600000) or «Removal»(ref-463899-S40002501852012041600000) .
- Partially drain coolant system below pressurized coolant recovery container. Refer to «Standard Procedure»(ref-463907-S41979752222012041600000) .
- Unplug coolant temperature sensor electrical connector. NOTE: Capture any residual coolant that may flow.
- Remove coolant temperature sensor (5).
When the Engine is cold and both the primary and secondary thermostats are closed. The coolant will circulate through the engine, heater system, and the bypass. The cooling system has no flow through the radiator
As the engine warms up, the primary thermostat will start to open at 82 °C (179 °F). Coolant will start to flow through the radiator oil cooler and transmission cooler. Coolant will flow through the transmission oil cooler only when the primary thermostat is fully open. The primary thermostat will fully open at 95 °C (203 °F).
The secondary thermostat will start to open at 95 °C (203 °F). This will increase the coolant flow through the cylinder block and cylinder head and the radiator. The secondary thermostat will fully open at 110 °C (230 °F).
If the thermostat is stuck open or allows coolant leakage through it, the engine will not operate at the proper temperature for obtaining engine fuel efficiency, performance and emissions levels. If this condition occurs, a diagnostic trouble code will be set and a MIL light will be turned on. Refer to the Powertrain Diagnostic Procedures information for further information and diagnostics provided.