SFI SYSTEM(w/o Canister Pump Module), Diagnostic DTC:P26CB71

DTC Code	DTC Name
P26CB71	Engine Coolant Pump Actuator Stuck

DESCRIPTION

Refer to DTC P26CA12.

Click here

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P26CB71	Engine Coolant Pump Actuator Stuck	Even though an operation request signal is being output, the engine water pump assembly does not rotate* (1 trip detection logic).	Lack of engine coolant Engine coolant leak Engine water pump assembly (water inlet housing) ECM	Comes on	DTC stored	SAE Code: P26CB

*: As the frequency signal (WPI) is 4 Hz when the engine water pump assembly is stopped to enable the ECM to detect an open or short in the signal line, the engine water pump assembly speed will be displayed as approximately 160 rpm even when the pump is stopped. If there is an open in the WPI circuit, the engine water pump speed will be displayed as 0 rpm.

Related Data List
DTC No.	Data List
P26CB71	Coolant Temperature Electric Water Pump Target Speed Electric Water Pump Speed

MONITOR DESCRIPTION

The ECM receives a frequency signal (WPI) from the engine water pump assembly and calculates the speed of the engine water pump assembly. The ECM outputs an operation duty signal (WPO) to steplessly control the speed of the engine water pump assembly. If the duty signal (WPI) indicates that the engine water pump assembly is stopped even though the ECM is outputting an operation duty signal (WPO), the ECM judges that the engine water pump assembly is stuck and stores this DTC.

As the frequency signal (WPI) is 4 Hz when the engine water pump assembly is stopped to enable the ECM to detect an open or short in the signal line, the engine water pump assembly speed will be displayed as approximately 160 rpm even when the pump is stopped.

MONITOR STRATEGY

Required Sensors/Components	Engine water pump assembly
Frequency of Operation	Continuous

CONFIRMATION DRIVING PATTERN

Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON [A].
Turn the GTS on.
Move the shift lever to P [B].
Start the engine and maintain the engine speed at 2500 rpm or more for at least 40 seconds [C].
Enter the following menus: Powertrain / Engine / Trouble Codes [D].
Read the pending DTCs.
Tech Tips
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Input the DTC: P26CB71.

Check the DTC judgment result.

GTS Display	Description
NORMAL	DTC judgment completed System normal
ABNORMAL	DTC judgment completed System abnormal
INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions

Tech Tips

If the judgment result is NORMAL, the system is normal.
If the judgment result is ABNORMAL, the system has a malfunction.
If the judgment result is INCOMPLETE, perform steps [B] through [D] again.

WIRING DIAGRAM

Refer to DTC P26CA12.

Click here

CAUTION / NOTICE / HINT

Tech Tips

As the frequency signal (WPI) is 4 Hz when the engine water pump assembly is stopped to enable the ECM to detect an open or short in the signal line, the engine water pump assembly speed will be displayed as approximately 160 rpm even when the pump is stopped.
Read Freeze Frame Data using the GTS. The ECM records vehicle and driving condition information as Freeze Frame Data the moment a DTC is stored. When troubleshooting, Freeze Frame Data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P26CB71)

Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Trouble Codes.

Read the DTCs.

Powertrain > Engine > Trouble Codes

Result

Result	Proceed to
DTC P26CB71 is output	A
DTC P26CB71 and P26CE37 are output	A
DTC P26CB71 and other DTCs are output	B

GO TO DTC CHART Click here

CHECK ENGINE COOLANT LEVEL IN RESERVOIR TANK

Check that the engine coolant level is between the FULL and LOW lines.

Click here

Result

Result	Proceed to
Engine coolant level is above the LOW line	A
Engine coolant level is below the LOW line	B

GO TO STEP 6 Click here

CHECK FOR ENGINE COOLANT LEAKS

Check the areas around the engine and heater for engine coolant leaks.

Click here

Tech Tips

If the engine oil is cloudy during the engine oil level gauge check, it means that engine coolant has entered the engine lubrication system.

OK
No leaks.

Result

Proceed to
OK
NG

REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA Click here

ADD ENGINE COOLANT

Fill the reservoir tank up to the FULL line with engine coolant.

Note

Make sure not to add engine coolant when the engine is hot.

Result

Proceed to
NEXT

GO TO STEP 6 Click here

REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA

Repair any engine coolant leaks.

Tech Tips

Add engine coolant and perform air bleeding after repair.

Result

Proceed to
NEXT

PERFORM ACTIVE TEST USING GTS (ACTIVATE THE ELECTRIC WATER PUMP)

Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Active Test / Activate the Electric Water Pump / Data List / Electric Water Pump Speed.

Powertrain > Engine > Active Test

Active Test Display

Activate the Electric Water Pump

Data List Display

Electric Water Pump Speed

Active Test Display
Activate the Electric Water Pump

Data List Display
Electric Water Pump Speed

According to the display on the GTS, read the Data List while performing the Active Test.

Standard

Active Test Operation	Electric Water Pump Speed
3000 rpm	2000 rpm or higher

Result

Proceed to
OK
NG

GO TO STEP 8 Click here

INSPECT ECM (INTERNAL CIRCUIT)

*a	Front view of wire harness connector (to Engine Water Pump Assembly (Water Inlet Housing))

Disconnect the engine water pump assembly (water inlet housing) connector.
Turn the ignition switch to ON.

Measure the resistance according to the value(s) in the table below.

Standard

Tester Connection	Condition	Specified Condition
C43-2 (SWP) - Body ground	Ignition switch ON	Resistance fluctuates*

Tech Tips

*: When the connector of the engine water pump assembly is disconnected, the ECM will enter fail-safe mode. When the ECM is in fail-safe mode, a continuous duty signal will be output and the resistance will fluctuate as the transistor inside the ECM is turned on an off.
If the resistance fluctuates while the ECM is in fail-safe mode after the connector of the engine water pump assembly is disconnected, it can be determined that the transistor is operating.
If the transistor is not operating, the ECM may be malfunctioning.
If the resistance fluctuates after turning the ignition switch ON, it can be determined that the ECM is in fail-safe mode.

Result

Proceed to
OK
NG

REPLACE ECM Click here

REPLACE ENGINE WATER PUMP ASSEMBLY (WATER INLET HOUSING)

Replace the engine water pump assembly (water inlet housing).

Click here

Tech Tips

When replacing any cooling system parts, if excessive deposits of rust or scale exist or the concentration of the engine coolant is abnormal, replace the engine coolant.

Result

Proceed to
NEXT

CLEAR DTC

Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs.

Powertrain > Engine > Clear DTCs

Turn the ignition switch off and wait for at least 30 seconds.

Result

Proceed to
NEXT

CHECK WHETHER DTC OUTPUT RECURS (DTC P26CB71)

Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine / Trouble Codes.

Read the DTCs.

Powertrain > Engine > Trouble Codes

Tech Tips

If no DTC is output, the repair has been successfully completed.

Result

Proceed to
NEXT

END