DTC P011A (K20C1) (2019 2020 2021)

DTC P011A:  Engine Coolant Temperature (ECT) Sensor 1 Circuit Range/Performance Problem

General Description 

Courtesy of HONDA, U.S.A., INC.

Courtesy of HONDA, U.S.A., INC.

The powertrain control module (PCM) monitors engine coolant temperature (ECT) sensor 1 for electrical malfunctions. In order to provide diagnosis the measured engine coolant temperature is monitored against expected engine coolant temperature at engine start. The expected engine coolant temperature is a modeled temperature which represents the lowest possible heating up of engine coolant temperature. The measured engine coolant temperature is always higher than expected temperature value in case of valid sensor. If the difference between the ECT sensor 1 output temperature and mean value of all temperature sensors at cold start is more than a specified value for a specified time, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type 

Execution	Once per driving cycle
Sequence	None
Duration	90 seconds or more
DTC Type	Two drive cycles, MIL on

Enable Conditions 

Condition	Minimum	Maximum
Engine off time	6 hours	-
State of the engine	Running

Malfunction Threshold 

The difference between the ECT sensor 1 output temperature and mean value of all temperature sensors at cold start is more than 44 deg.F (24 deg.C) for at least 90 seconds.

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.

• ECT sensor 1 failure
• PCM internal circuit failure

Confirmation Procedure 

Operating Condition 

Start the engine and drive the vehicle for at least 2 minutes.

• Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.

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.