Heater wont turn off

Hi - Dave here, contributing to RepairPal and providing expert advice since 2010. This sounds like a malfunction with the temperature control system. This could be an internal failure of the control unit itself. Check for his circuit protection issues like blown fuses. Other than that, a diagnostic tester would be required (Ford IDS or related) to check for any trouble codes related to the system.. https://repairpal.com/auto-repair-near-me Click the link to find some shops near you who can help out!