Pinpoint Test H: Insufficient, Erratic Or No Heat
WARNING: This page is about a different car, the 2006 Mercury Milan, 2006 Lincoln Zephyr, and 2006 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
- H1 CHECK FOR CORRECT ENGINE COOLANT LEVEL
- Key in OFF position.
- Check the engine coolant level when hot and cold.
- Is the engine coolant at the correct level (hot/cold) as indicated on the engine coolant recovery reservoir?
Yes : GO to H3.
No : GO to H2.
- H2 CHECK THE ENGINE COOLING SYSTEM FOR LEAKS
- Pressure test the cooling system for leaks. Refer to ENGINE COOLING .
- Does the engine cooling system leak?
Yes : REPAIR the engine coolant leak. TEST the system for normal operation.
No : GO to H3.
- H3 CHECK FOR COOLANT FLOW TO THE HEATER CORE WARNING: The heater core inlet hose will become too hot to handle and may cause serious burns if the system is working correctly.
- Run the engine until it reaches normal operation temperature. Select the floor position on the control assembly. Set the temperature control to full warm.
- Feel the heater core inlet hose to see if it is hot.
- Is the heater core inlet hose hot?
Yes : GO to H4.
No : REFER to ENGINE COOLING to check cooling system function.
- H4 CHECK FOR A PLUGGED OR RESTRICTED HEATER CORE WARNING: The heater core outlet hose will become too hot to handle and may cause serious burns if the system is operating correctly.
- Feel the heater core outlet hose to see if it is hot.
- Is the heater core outlet hose hot?
Yes : GO to PINPOINT TEST K and diagnose for a blend door actuator.
No : INSTALL a new heater core. TEST the system for normal operation.