What is the meaning of OBD-II code P0118, and what are the possible causes and solutions for this code to be generated?

The code P0118 is a standard code used by the OBD-II system, which indicates that the Engine Control Module has detected that the temperature readings from the ECT sensor are either above 4.91 volts or below -40°C (-40°F). There are several possible causes for a P0118 code, such as: -Faulty Engine Coolant Temperature Sensor -Corroded or Rusty Engine Coolant -Engine Coolant Temperature Wiring or Connections that are faulty or corroded To diagnose the problem, a mechanic will inspect for disconnected or damaged connectors, scan for codes and freeze frame data, clear OBD-II fault codes, and test for open circuits by connecting pins and checking for a temperature above 284 deg F. They will repair any issues found, such as bent pins, corrosion, or a faulty ECT sensor. The resolution to the P0118 code depends on the root cause but may involve fixing the ECT connector, repairing the wiring open circuit, or replacing the ECT sensor. The majority of causes for code P0118 are related to an open circuit failure in the ECT sensor.