SFI SYSTEM, Diagnostic DTC:P261B, P261C, P261D

DTC Code DTC Name
P261B Engine Coolant Pump "B" Control Malfunction
P261C Engine Coolant Pump "B" Control Circuit Low
P261D Engine Coolant Pump "B" Control Circuit High

DESCRIPTION

The ECM controls the engine water pump assembly by calculating the necessary amount of coolant flow based on engine coolant temperature, engine speed and vehicle speed information. The speed of the engine water pump assembly is controlled steplessly using duty cycle signal sent from the ECM. This optimal control enhances warm-up performance and reduces cooling losses, thus reducing the specific fuel consumption of the engine.

DTC No. DTC Detection Condition Trouble Area
P261B

Engine water pump speed is less than 900 rpm while the engine water pump assembly is operating

(1 trip detection logic)

  • Open or short in engine water pump assembly circuit

  • Engine water pump assembly

  • ECM
P261C

Engine water pump output voltage is less than specified value while the engine water pump assembly is operating

(1 trip detection logic)

  • Short in engine water pump assembly circuit

  • Engine water pump assembly

  • ECM
P261D

Engine water pump output voltage is higher than specified value while the engine water pump assembly is operating

(1 trip detection logic)

  • Open in engine water pump assembly circuit

  • Engine water pump assembly

  • ECM

WIRING DIAGRAM

A003UBIE01

INSPECTION PROCEDURE

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (ACTIVATE THE ELECTRIC WATER PUMP)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the Electric Water Pump.

    5. Touch the engine water pump assembly and check that the pump is operating (vibrating).

      OK
      The engine water pump assembly is operating (vibrating).

    NG

    CHECK ENGINE WATER PUMP ASSEMBLY (POWER SOURCE VOLTAGE) Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (ENGINE WATER PUMP ASSEMBLY - ECM)

    Tech Tips

    Confirm a good connection at the engine water pump assembly and ECM connectors.


    1. Disconnect the engine water pump assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      B136-2 (NWP) - A50-11 (WPI) Always Below 1 Ω
      B136-4 (SWP) - A50-10 (WPO) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B136-2 (NWP) or A50-11 (WPI) - Body ground Always 10 kΩ or higher
      B136-4 (SWP) or A50-10 (WPO) - Body ground Always 10 kΩ or higher

    4. Reconnect the engine water pump assembly connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE WATER PUMP ASSEMBLY - ECM)

    OK

  3. CHECK ECM (WPI VOLTAGE)


    1. A003RL7E08
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Engine Water Pump Assembly)

      Disconnect the engine water pump assembly connector.

    2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      B136-2 (NWP) - Body ground Power switch on (IG) 11 to 14 V

    4. Reconnect the engine water pump assembly connector.


    NG

    REPLACE ECM Click here

    OK

    REPLACE ENGINE WATER PUMP ASSEMBLY Click here

  4. CHECK ENGINE WATER PUMP ASSEMBLY (POWER SOURCE VOLTAGE)

    Tech Tips

    Confirm a good connection at the engine water pump assembly and ECM connectors.


    1. A003RL7E09
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Engine Water Pump Assembly)

      Disconnect the engine water pump assembly connector.

    2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      B136-1 (+B) - Body ground Power switch on (IG) 11 to 14 V

    4. Reconnect the engine water pump assembly connector.


    NG

    INSPECT ENG W/P RELAY Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (ENGINE WATER PUMP ASSEMBLY - BODY GROUND)


    1. Disconnect the engine water pump assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Switch Condition Specified Condition
      B136-5 (PGND) - Body ground Always Below 1 Ω

    3. Reconnect the engine water pump assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE WATER PUMP ASSEMBLY - BODY GROUND)

    OK

  6. CHECK HARNESS AND CONNECTOR (ENGINE WATER PUMP ASSEMBLY - ECM)


    1. Disconnect the engine water pump assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      B136-2 (NWP) - A50-11 (WPI) Always Below 1 Ω
      B136-4 (SWP) - A50-10 (WPO) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B136-2 (NWP) or A50-11 (WPI) - Body ground Always 10 kΩ or higher
      B136-4 (SWP) or A50-10 (WPO) - Body ground Always 10 kΩ or higher

    4. Reconnect the engine water pump assembly connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE WATER PUMP ASSEMBLY - ECM)

    OK

  7. REPLACE ENGINE WATER PUMP ASSEMBLY


    1. Replace the engine water pump assembly Click here.


    NEXT

  8. CHECK WHETHER DTC OUTPUT RECURS (DTC P261B, P261C OR P261D)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on.

    3. Turn the tester on.

    4. Put the engine in inspection mode Click here.

    5. Start the engine and warm it up (until the engine coolant temperature is 75°C (167°F) or more).

    6. Idle the engine for 20 seconds or more.

    7. Enter the following menus: Powertrain / Engine and ECT / DTC.

    8. Read the DTCs.

      Result
      Result Proceed to
      DTC P261B, P261C or P261D is output A
      DTC is not output B

    B

    END

    A

    REPLACE ECM Click here

  9. INSPECT ENG W/P RELAY


    1. A003UPIE01

      Remove the ENG W/P relay from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage is not applied between terminals 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage is applied between terminals 1 and 2 Below 1 Ω

    3. Reinstall the ENG W/P relay to the engine room relay block.


    NG

    REPLACE ENG W/P RELAY

    OK

  10. CHECK HARNESS AND CONNECTOR (ENG W/P RELAY - ENGINE WATER PUMP ASSEMBLY)


    1. Remove the ENG W/P relay from the engine room relay block.

    2. Disconnect the engine water pump assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      5 (ENG W/P relay) - B136-1 (+B) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      5 (ENG W/P relay) or B136-1 (+B) - Body ground Always 10 kΩ or higher

    4. Reinstall the ENG W/P relay.

    5. Reconnect the engine water pump assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENG W/P RELAY - ENGINE WATER PUMP ASSEMBLY)

    OK

  11. CHECK ENG W/P RELAY (POWER SOURCE VOLTAGE)


    1. A003T8KE01
      Text in Illustration
      *1 Engine Room Relay Block

      Remove the ENG W/P relay from the engine room relay block.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3 (ENG W/P relay) - Body ground Always 11 to 14 V

    3. Reinstall the ENG W/P relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENG W/P RELAY - BATTERY)

    OK

  12. CHECK HARNESS AND CONNECTOR (ENG W/P RELAY - BODY GROUND)


    1. Remove the ENG W/P relay from the engine room relay block.

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

      Standard Resistance (Check for Open)
      Tester Connection Switch Condition Specified Condition
      1 (ENG W/P relay) - Body ground Always Below 1 Ω

    3. Reinstall the ENG W/P relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENG W/P RELAY - BODY GROUND)

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENG W/P RELAY - NO. 2 INTEGRATION RELAY)