DTC P26A3

DTC P26A3: Electric Water Valve Malfunction

General Description

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

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

The engine coolant temperature (ECT) sensor 1 measures the engine coolant temperature and is used for fuel and ignition control. If the electric water valve fails, the ECT sensor 1 value will increase due to the engine coolant is heated by the electric coolant heater even when the engine is not warmed up. When the temperature of ECT sensor 1 rises while the engine is stopped, the powertrain control module (PCM) detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type

Execution	Once per driving cycle
Sequence	None
Duration	10 second or more
DTC Type	Two drive cycles, MIL on

Enable Conditions

Condition	Minimum	Maximum
Elapsed time after turn the vehicle to the ON mode	5 seconds	-
Engine coolant temperature [ECT Sensor 1]	158 deg.F (70 deg.C)	-
Other	Before starting the engine

[ ]: HDS Parameter

Malfunction Threshold

When the engine coolant temperature rises before an engine start.

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.

Electric water valve stuck
Electric water valve leak
Electric water valve position sensor line failure
Electric valve motor failure
Climate control unit failure
Heater core temperature sensor failure
B-CAN line failure
Gauge control module failure

Confirmation Procedure

Operating Condition

Turn the vehicle to the ON mode, and wait for at least 15 seconds.

With the HDS

None.

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 12 volt battery.