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Coolant Temperature Sensor / Switch HVAC: Service and Repair

Temperature Control Lockout Valve and Switch

The temperature control lockout valve and switch is threaded and screws into a fitting in the heater core inlet tube in the engine compartment.

Removal and Installation

1. Disconnect two-wire connector from temperature control lockout valve and switch.

2. Partially drain coolant from radiator.

3. Remove threaded switch by turning out of fitting in heater tube.











4. Apply Pipe Sealant with Teflon� D8AZ-19554-A or equivalent meeting Ford specification WSK-M2G350-A2 to switch threads and install into fitting. Tighten to 11-19 N.m (9-14 lb4t).

5. Attach electrical connector to top of temperature control lockout valve and switch.

6. Refill radiator.