P1121 — Engine Coolant sensor out of range/ECT Sensor Out Of Self Test Range

What it means

P1121 is an OBD-II diagnostic trouble code: Engine Coolant sensor out of range/ECT Sensor Out Of Self Test Range.

Typical fix

Confirm the code with an OBD-II scanner, then inspect the component or circuit named above. Consult a vehicle-specific service manual for the full diagnostic and repair procedure.