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DTC P0115

DTC P0115:  Engine Coolant Temperature (ECT) Sensor 1 Out of Range

General Description 

GHH343841Courtesy of HONDA, U.S.A., INC.
GHH343842Courtesy of HONDA, U.S.A., INC.

Engine coolant temperature (ECT) sensor 1 is used for air/fuel ratio feedback control, ignition timing control, idle speed control, and other functions. The ECT sensor 1 resistance varies depending on the engine coolant temperature. As the engine coolant cools, the ECT sensor 1 resistance increases, and the powertrain control module (PCM) detects a high signal voltage. As the engine coolant warms, the ECT sensor 1 resistance decreases, and the PCM detects a low signal voltage. If the ECT sensor 1 output voltage is a specified value for a set time, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type 

Execution Continuous
Sequence None
Duration 6 seconds or more
DTC Type Two drive cycles, MIL on

Enable Conditions 

Condition  
Engine start/stop button ON mode

Malfunction Threshold 

The ECT sensor 1 output voltage [ECT SENSOR 1] is 0.12 V or less for at least 6 seconds.

[ ]: HDS Parameter

Possible Cause 

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Diagnosis Details 

Conditions for setting the DTC 

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC 

The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.