Pinpoint Test F : Insufficient, Erratic Or No Heat: Notes
WARNING: This page is about a different car, the 2018 Ford F-550 Super Duty, 2018 Ford F-450 Super Duty, 2018 Ford F-350 Super Duty, and 2018 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
Normal Operation and Fault Conditions
When the engine is at operating temperature hot coolant flows from the coolant pump through the heater core and back to the coolant pump. Correct coolant temperatures are critical for good heater performance.
Possible Sources
- Wiring, terminals or connectors
- Temperature blend door actuator
- Air trapped in the coolant system
- Heater core
Visual Inspection and Diagnostic Pre-checks
- Inspect for low engine coolant level.