P0117
DTC P0115 Engine Coolant Temperature CircuitDTC P0117 Engine Coolant Temperature Circuit Low Input
DTC P0118 Engine Coolant Temperature Circuit High Input
DESCRIPTION
DTC Detection Condition:
A thermistor is built into the Engine Coolant Temperature (ECT) sensor and changes the resistance value according to the engine coolant temperature.
The structure of the sensor and connection to the ECM is the same as the Intake Air Temperature (IAT) sensor.
HINT: If the ECM detects the DTC P0115, P0117 or P0118, it operates the fail-safe function in which the ECT is assumed to be 80 °C (176 °F).
HINT: After confirming DTC "P0115, P0117 or P0118", use the intelligent tester to confirm the engine coolant temperature in the "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL".
MONITOR DESCRIPTION
Monitor Strategy:
Typical Enabling Conditions:
Typical Malfunction Thresholds:
Component Operating Range:
The Engine Coolant Temperature (ECT) sensor is used to monitor the engine coolant temperature. The ECT sensor has a thermistor that varies its resistance depending on the temperature of the engine coolant. When the coolant temperature is low, the resistance in the thermistor increases. When the temperature is high, the resistance drops. The variations in resistance are reflected in the voltage output from the sensor. The ECM monitors the sensor voltage and uses this value to calculate the ECT. When the sensor output voltage deviates from the normal operating range, the ECM interprets this as a fault in the ECT sensor and sets a DTC.
Example: When the ECM calculates that the ECT is -40 °C (-40 °F) (P0118) or more than 140 °C (284 °F) (P0117) and if either condition continues for 0.5 seconds or more, the ECM will set a DTC.
Wiring Diagram:
Step 1-2:
Step 3(Continued)-4:
Step 5:
INSPECTION PROCEDURE
HINT:
- If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
- Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.