Pinpoint Test N : Insufficient, Erratic Or No Heat: Notes
WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
Normal Operation and Fault Conditions
Warm coolant flows from the engine through the heater core and back to the engine. Proper coolant temperatures are critical for good heater performance.
Possible Sources
- Plugged or partially plugged heater core
- Low engine coolant level
- Temperature blend door actuator(s)
- Temperature blend door(s) binding or stuck