2006 DODGE RAM SRT-10 cooling

When Monitored:
Ignition on and engine running.
Set Condition:
An open or shorted condition in the Hydraulic Fan Solenoid control circuitis detected by the Powertrain Control
Module.
Possible Causes
RADIATOR FAN INOP
(K342) FUSED ASD RELAY OUTPUT CIRCUIT
(C240) COOLING FAN CONTROL CIRCUIT OPEN
(C240) COOLING FAN CONTROL CIRCUIT SHORTED TO GROUND
HYDRAULIC FAN
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
1.RADIATOR FAN INOP
Ignition on, engine not running.
With the scan tool, perform the Hydraulic Fan Solenoid Test found under Engine Test and Systems Test.
Does the Radiator Fan operate properly?
Ye s>>
Refer to the INTERMITTENT CONDITIONSymptom (Diagnostic Procedure).
Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 2
2.(K342) FUSED ASD RELAY OUTPUT CIRCUIT
Turn the ignition off.
Disconnect the Fan Solenoid harness connector.
Ignition on, engine not running.
With the scan tool, actuate the ASD Relay.
Using a 12-volt test light connect to ground, probe the (K342) Fused
ASD Relay Output circuit at the fan solenoid.
Does the test light illuminate brightly when the ASD Relay is
actuated?
Ye s>>
Go To 3
No>>
Repair the open or short to ground in the (K342) Fused
ASD Relay Output circuit. Inspect the related fuse and
repair as necessary.
Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

3.(C240) COOLING FAN SOLENOID CIRCUIT OPEN
Turn the ignition off.
Disconnect the PCM harness connectors.
Measure the resistance of the (C240) Cooling Fan Solenoid Control cir-
cuit from the fan harness connector to the PCM harness connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 4
No>>
Repair the open in the (C240) Cooling Fan Control circuit.
Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 -
ENGINE - STANDARD PROCEDURE)
4.(C240) COOLING FAN CONTROL CIRCUIT SHORT TO GROUND
Measure the resistance between ground and the (C240) Cooling Fan
Control circuit.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (C240) Cooling Fan Con-
trol circuit.
Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 -
ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
5.HYDRAULIC FAN SOLENOID
Remove the ASD Relay and connect a jumper wire between the (K342) ASD Relay Output terminal and the (A14)
Fused B+ circuit to keep the ASD Output circuit powered up for this step.
Connect another jumper wire to the (C240) Hydraulic Fan Solenoid Control circuit in the PCM harness connector.
Momentarily connect the other end of the jumper wire to ground.
NOTE: Remove the jumper wires before continuing.
Did the solenoid actuate?
Ye s>>
Go To 6
No>>
Replace the Hydraulid Radiator Fan.
Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

REMOVAL
1. Disconnect the battery negative cable.
2. Remove air cleaner assembly.
3. Remove radiator core support bracket.
4. Remove fan shroud with viscous fan assembly.
5. Remove drive belt.
6. Remove A/C compressor (2) and secure away from
engine.
7. Remove generator (3) and secure away from
engine.
NOTE: Do NOT remove the phenolic pulley from
the P/S pump. It is not required for P/S pump
removal.
8. Remove power steering pump with lines attached
and secure away from engine.
9. Drain cooling system.
10. Disconnect the heater hoses from the engine.
11. Disconnect heater hoses from heater core and
remove hose assembly.
12. Disconnect throttle and speed control cables.
13. Remove upper radiator hose from engine.
14. Remove lower radiator hose from engine.
15. Remove radiator/cooling module assembly.
16. Disconnect the engine to body ground straps at
theleftsideofcowl.

25. Connect the engine wiring harness at the follow-
ing points :
Intake air temperature (IAT) sensor (4)
Fuel Injectors
Throttle Position (TPS) Switch (2)
Idle Air Control (IAC) Motor (3)
Engine Oil Pressure Switch
Engine Coolant Temperature (ECT) Sensor
Manifold Absolute Pressure MAP) Sensor
Camshaft Position (CMP) Sensor
Coil Over Plugs
Crankshaft Position Sensor
26. Reinstall the radiator/cooling module assembly.
27. Connect lower radiator hose.
28. Connect upper radiator hose.
29. Connect throttle and speed control cables.
30. Install the heater hose assembly.
31. Install coolant recovery bottle.
32. Install the power steering pump.
33. Install the generator (3).

34. Install the A/C compressor (2).
35. Install the drive belt.
36. Install the fan shroud with the viscous fan assem-
bly.
37. Install the radiator core support bracket.
38. Install the air cleaner assembly.
39. Refill the engine cooling system.
40. Recharge the air conditioning.
41. Check and fill engine oil.
42. Connect the battery negative cable.
43. Start the engine and check for leaks.
SPECIFICATIONS
SPECIFICATIONS - 3.7L ENGINE
GENERAL SPECIFICATIONS
DESCRIPTION SPECIFICATION
Type 90°SOHCV612Valve
Number of Cylinders 6
Firing Order 1-6-5-4-3-2
Lead Cylinder No. 1 Left Bank
Compression Ratio 9.6:1
Max. Variation Between Cylinders 25%
Metric Standard
Displacement 3.7 Liters 226 Cubic Inches
Bore 93.0 mm 3.66 in.
Stroke 90.8 mm 3.40 in.
Horsepower 211 @ 5200 RPM
Torque 236ft. lbs.@4000 PRM
Compression Pressure 1172-1551 kPa 170-225 psi
CYLINDER BLOCK
DESCRIPTION SPECIFICATION
Metric Standard
Bore Diameter 93.013 ± .0075 mm 3.6619 ± 0.0003 in.
Out of Round (MAX) 0.076 mm 0.003 in.
Taper (MAX) 0.051 mm 0.002 in.
PISTONS

HEAD-CYLINDER-LEFT
DIAGNOSIS AND TESTING - CYLINDER HEAD GASKET
A cylinder head gasket leak can be located between adjacent cylinders or between a cylinder and the adjacent
water jacket.
Possible indications of the cylinder head gasket leaking between adjacent cylinders are:
Loss of engine power
Engine misfiring
Poor fuel economy
Possible indications of the cylinder head gasket leaking between a cylinder and an adjacent water jacket are:
Engine overheating
Loss of coolant
Excessive steam (white smoke) emitting from exhaust
Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is leaking between adjacentcylinders, follow the procedures in Cyl-
inder Compression Pressure Test (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING). An engine cylinder head
gasket leaking between adjacent cylinders will result in approximately a50 - 70% reduction in compression pres-
sure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE ENGINE IS OPERATING WITH COOLANT PRESSURE CAP
REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure cap. Start the engine andallow it to warm up until thermostat
opens.
If a large combustion/compression pressure leak exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN PLACE, PRESSURE WILL BUILD UP FAST.EXCESSIVE
PRESSURE BUILT UP, BY CONTINUOUS ENGINE OPERATION, MUST BE RELEASED TO A SAFE PRESSURE
POINT. NEVER PERMIT PRESSURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to pressure cap neck. Start the engine and observe the tester’s
pressure gauge. If gauge pulsates with every power stroke of a cylinder a combustion pressure leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also be checked by using Bloc-Chek Kit C-3685-A or equivalent.
Perform test following the procedures supplied with the tool kit.
REMOVAL
1. Disconnect the negative cable from the battery.
2. Raise the vehicle on a hoist.
3. Disconnect the exhaust pipe at the left side exhaust manifold.
4. Drain the engine coolant (Refer to 7 - COOLING - STANDARD PROCEDURE).
5. Lower the vehicle.
6. Remove the intake manifold (Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANIFOLD - REMOVAL).

7. Remove the master cylinder and booster assembly (Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/POWER
BRAKE BOOSTER - REMOVAL).
8. Remove the cylinder head cover (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) -
REMOVAL).
9. Remove the fan shroud and fan blade assembly
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
REMOVAL).
10. Remove accessory drive belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
11. Remove the power steering pump and set aside.
12. Rotate the crankshaft until the damper timing
mark is aligned with TDC indicator mark (2).
13. Verify the V6 mark on the camshaft sprocket is at the 12 o’clock position. Rotate the crankshaft one turn if
necessary.
14. Remove the crankshaft damper (Refer to 9 - ENGINE/ENGINE BLOCK/VIBRATION DAMPER - REMOVAL).
15. Remove the timing chain cover (Refer to 9 - ENGINE/VALVE TIMING/TIMINGBELT / CHAIN COVER(S) -
REMOVAL).

2. Position the new cylinder head gasket on the locat-
ing dowels.
CAUTION: When installing cylinder head, use care
not damage the tensioner arm or the guide arm.
3. Position the cylinder head onto the cylinder block.
Make sure the cylinder head seats fully over the
locating dowels.
NOTE: The four smaller cylinder head mounting
bolts require sealant to be added to them before
installing. Failure to do so may cause leaks.
4. Lubricate the cylinder head bolt threads with clean
engine oil and install the eight M11 bolts.
5. Coat the four M8 cylinder head bolts withMopar
Lock and Seal Adhesivethen install the bolts.
NOTE: The cylinder head bolts are tightened using
an angle torque procedure, however, the bolts are
not a torque-to-yield design.
6. Tighten the bolts in sequence using the following steps and torque values:
Step 1: Tighten bolts 1-8, 27 Nꞏm (20 ft. lbs.).
Step 2: Verify that bolts 1-8, all reached 27 Nꞏm (20 ft. lbs.), by repeatingstep 1 without loosening the bolts.
Tightenbolts9thru12to14Nꞏm(10ft.lbs.).
Step 3: Tighten bolts 1-8, 90 degrees.
Step 4: Tighten bolts 1-8, 90 degrees, again. Tighten bolts 9-12, 26 Nꞏm (19ft. lbs.)
7. Position the secondary chain onto the camshaft drive gear, making sure one marked chain link is on either side
of the V6 mark on the gear then using Special Tool 8428 Camshaft Wrench, position the gear onto the camshaft.
CAUTION: Remove excess oil from camshaft sprocket retaining bolt before reinstalling bolt. Failure to do so
may cause over-torqueing of bolt resulting in bolt failure.
8. Install the camshaft drive gear retaining bolt.
9. Install the left side secondary chain guide (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - INSTALLATION).
10. Install the cylinder head access plug.
11. Re-set and install the left side secondary chain tensioner (Refer to 9 -ENGINE/VALVE TIMING/TIMING BELT/
CHAIN AND SPROCKETS - INSTALLATION).
12. Remove Special Tool 8429.
13. Install the timing chain cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) -
INSTALLATION).
14. Install the crankshaft damper (Refer to 9 - ENGINE/ENGINE BLOCK/VIBRATION DAMPER - INSTALLATION).
Tighten damper bolt 175 Nꞏm (130 Ft. Lbs.).
15. Install the power steering pump.
16. Install the fan blade assembly and fan shroud (Refer to 7 - COOLING/ENGINE/RADIATOR FAN - INSTALLA-
TION).
17. Install the cylinder head cover (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - INSTAL-
LATION).
18. Install the master cylinder and booster assembly (Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/POWER
BRAKE BOOSTER - INSTALLATION).
19. Install the intake manifold (Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANIFOLD - INSTALLATION).
20. Refill the cooling system (Refer to 7 - COOLING - STANDARD PROCEDURE).