Heater Control Valve: Service and Repair

Coolant Bypass Valve Replacement (6.6L)

Special Tools

J 38185 Hose Clamp Pliers

Removal Procedure

1. Remove the air cleaner assembly.
2. Remove the upper fan shroud.
3. Remove the accumulator.
4. Remove the vacuum hose from the coolant bypass valve.




5. Drain the engine coolant. Refer to Cooling System Draining and Filling (Static Fill) Cooling System Draining and Filling (Vac N Fill).
6. Reposition the heater inlet hose clamp and the heater outlet hose clamp from the coolant bypass valve using the J 38185.
7. Remove the heater inlet hose and the heater outlet hose from the coolant bypass valve.




8. Reposition the heater inlet hose clamp and the heater outlet hose clamp from the heater core using the J 38185.
9. Remove the heater inlet hose and the heater outlet hose from the heater core.
10. Remove the coolant bypass valve assembly from the vehicle.

Installation Procedure




1. Install the coolant bypass valve assembly to the vehicle.
2. Install the heater inlet hose and the heater outlet hose to the heater core.
3. Reposition the heater inlet hose clamp and the heater outlet hose clamp to the heater core using the J 38185.




4. Install the heater inlet hose and the heater outlet hose to the coolant bypass valve.
5. Reposition the heater inlet hose clamp and the heater outlet hose clamp to the coolant bypass valve using the J 38185.
6. Install the vacuum hose to the coolant bypass valve.
7. Install the accumulator.
8. Fill the cooling system. Refer to Cooling System Draining and Filling (Static Fill) Cooling System Draining and Filling (Vac N Fill).
9. Install the upper fan shroud.
10. Install the air cleaner.