P0117

DTC P0115 Engine Coolant Temperature Circuit
DTC 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: Confirm the ECT using the intelligent tester. Enter the given menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / COOLANT TEMP.

MONITOR DESCRIPTION

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

Component Operating Range:

The 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 output voltage 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 that either condition continues for 0.5 seconds or more, the ECM will set a DTC.

This monitor runs for 0.5 seconds after the engine switch is turned on (IG).

Wiring Diagram:

Step 1:

Step 2-3:

Step 3(Continued)-5:

INSPECTION PROCEDURE