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critical Ford
Error Code ENGINE COOLANT TEMPERATURE (RTT)
Indicates that the engine coolant temperature is high, necessitating immediate action to prevent damage.
? What Causes This
Hot Weather driving conditions or cooling system malfunction like clogged radiator, low coolant levels or fan failure.
✓ How to Fix It
Stop vehicle as soon as possible and ensure proper engine cooling before proceeding - consult with a service technician immediately upon identification of any fault.
Source: page 18 of the official manual
From the manual
This error code appears in:
Ford F 150 2009 2014 Fuses And Fuse Box Diagram And Location