P0116

DTC P0116 Engine Coolant Temperature (ECT) Sensor Performance

Circuit Description

The engine coolant temperature (ECT) sensor is installed to the thermostat housing. The ECT sensor is a variable resistor and it measures the temperature of the engine coolant. If the ECM detects that the difference of engine coolant temperature is smaller than the calculated range during the predetermined conditions this DTC will set. This DTC will only run once per driving cycle within the enabling conditions.

Condition for Running the DTC

^ DTCs P0117 P0118 P0335 P0336 P0500 P0602 P0652 P0653 P1125 and P268A are not set.
^ The ignition switch is ON.
^ The engine runtime is longer than 10 minutes.
^ The engine speed is more than 1300 RPM for longer than 2 minutes.
^ The vehicle speed is more than 25 MPH (40 km/h) for longer than 2 minutes.
^ The accumulated fuel injection quantity since engine start is more than a threshold.

Condition for Setting the DTC

^ The ECM detects that the difference of maximum and minimum engine coolant temperature is less than 1.8°F (1°C) for longer than 5 seconds.

Action Taken When the DTC Sets

^ The ECM illuminates the MIL when the diagnostic runs and fails. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type A.
^ The ECM limits fuel injection quantity.
^ The ECM inhibits EGR control.
^ The ECM inhibits DPF regeneration control.
^ The ECM inhibits cruise control.

Condition for Clearing the DTC

^ Refer to DTC Type Definitions for Condition for Clearing the MIL/DTC - Type A.

Diagnostic Aids

^ After starting the engine the ECT should rise steadily to about 80 to 85°C (176 to 185°F) then stabilize when the thermostat opens.

^ Use the Temperature vs. Resistance table to test the ECT sensor at various temperature levels to evaluate the possibility of a skewed sensor. A skewed sensor could result in poor driveability concerns.

Circuit/System Testing DTC P0116