M20D-FKS ENGINE CONTROL SFI SYSTEM P26CB71 Engine Coolant Pump Actuator Stuck
DESCRIPTION
Refer to DTC P26CA12.
| 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: 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.
| 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
- HINT:
- ·
After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
·When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
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.
- HINT:
- ·
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 |
- HINT:
- ·
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.
·[A] to [D]: Normal judgment procedure.
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
·When clearing the permanent DTCs, do not disconnect the cable from the battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
WIRING DIAGRAM
Refer to DTC P26CA12.
CAUTION / NOTICE / HINT
- HINT:
- ·
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
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
- 50001 372
- Result:
Result Proceed to DTC P26CB71 is output A DTC P26CB71 and P26CE37 are output DTC P26CB71 and other DTCs are output B
A
B
Check that the engine coolant level is between the FULL and LOW lines.
- Result:
Result Proceed to Engine coolant level is above the LOW line A Engine coolant level is below the LOW line B
A
B
Check the areas around the engine and heater for engine coolant leaks.
- HINT:
-
If the engine oil is cloudy during the engine oil level dipstick check, it means that engine coolant has entered the engine lubrication system.
- OK:
No leaks.
- Result:
Proceed to OK NG
OK
NG
Fill the reservoir tank up to the FULL line with engine coolant.
- NOTICE:
-
Make sure not to add engine coolant when the engine is hot.
- Result:
Proceed to NEXT
NEXT
Repair any engine coolant leaks.
- HINT:
-
Add engine coolant and perform air bleeding after repair.
- Result:
Proceed to NEXT
NEXT
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 - 50004 372 42 359
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
OK
NG
| *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.
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.
- Powertrain > Engine > Active Test
-
Tester Display Activate the Electric Water Pump - 50004 372 42
Operate the engine water pump assembly (water inlet housing) using the Active Test function and measure the resistance according to the value(s) in the table below.
- Standard:
Tester Connection GTS Operation Specified Condition C74-3 (SWP) - Body ground 3000 rpm Resistance fluctuates*
- HINT:
-
*: Using the Active Test, duty control of the transistors in the ECM will be performed. Due to the duty control, resistance of the SWP terminal will be unstable during the Active Test. If the resistance fluctuates while performing the Active Test, it can be determined that the transistor is operating. If the transistor does not operate during the Active Test, the ECM may be malfunctioning.
- Result:
Proceed to OK NG
OK
NG
Replace the engine water pump assembly (water inlet housing).
- HINT:
-
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
NEXT
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs.
- Powertrain > Engine > Clear DTCs
- 50002 372
Turn the ignition switch off and wait for at least 30 seconds.
- Result:
Proceed to NEXT
NEXT
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
- 50001 372
- HINT:
-
If no DTC is output, the repair has been successfully completed.
- Result:
Proceed to NEXT
NEXT