LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2020 >> UX 200 Luxury >> Repair and Diagnosis >> External Pages >> Different car >> Section 25 (Engine Control System (SFI) (M20A-FXS) - Diagnostic Codes (5 Of 6) (Hybrid)) >> SFI System >> DTC P26CA-31: Engine Coolant Pump No Signal [10/2018 - ] >> Procedure

DTC P26CA-31: Engine Coolant Pump No Signal [10/2018 - ]: Procedure

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus UX 250h, 2023 Lexus UX 250h, 2022 Lexus UX 250h, 2021 Lexus UX 250h, and 2020 Lexus UX 250h. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF WATER INLET HOUSING WITH WATER PUMP SUB-ASSEMBLY) 
    GTY805757Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Water Inlet Housing with Water Pump Sub-assembly)
    1. Disconnect the water inlet housing with water pump sub-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 Condition Specified Condition
      C17-5 (NWP) - Body ground Power switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  8

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (WATER INLET HOUSING WITH WATER PUMP SUB-ASSEMBLY - BODY GROUND) 
    1. Disconnect the water inlet housing with water pump sub-assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C17-3 (PGN2) - Body ground Always Below 1 Ω
      C17-6 (PGND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK TERMINAL VOLTAGE (POWER SOURCE OF WATER INLET HOUSING WITH WATER PUMP SUB-ASSEMBLY) 
    GTY805758Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Water Inlet Housing with Water Pump Sub-assembly)
    1. Disconnect the water inlet housing with water pump sub-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 Condition Specified Condition
      C17-1 (+B2) - Body ground Power switch on (IG) 11 to 14 V
      C17-4 (+B) - Body ground Power switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE WATER INLET HOUSING WITH WATER PUMP SUB-ASSEMBLY. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    NG 

    See step  4

  4. INSPECT EFI-MAIN NO. 3 RELAY 
    1. Inspect the EFI-MAIN NO. 3 relay.

      Refer to ON-VEHICLE INSPECTION [10/2018 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE EFI-MAIN NO. 3 RELAY 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (POWER SOURCE OF EFI-MAIN NO. 3 RELAY) 
    GTY804054Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 1 Engine Room Relay Block and Junction Block Assembly
    *2 EFI-MAIN NO. 3 Relay
    1. Remove the EFI-MAIN NO. 3 relay from the No. 1 engine room relay block and junction block assembly.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      3 (EFI-MAIN NO. 3 relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - EFI-MAIN NO. 3 RELAY) 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 3 RELAY - BODY GROUND) 
    1. Remove the EFI-MAIN NO. 3 relay from the No. 1 engine room relay block and junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1 (EFI-MAIN NO. 3 relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 3 RELAY - WATER INLET HOUSING WITH WATER PUMP SUB-ASSEMBLY) 
    1. Remove the EFI-MAIN NO. 3 relay from the No. 1 engine room relay block and junction block assembly.
    2. Disconnect the water inlet housing with water pump sub-assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      5 (EFI-MAIN NO. 3 relay) - C17-1 (+B2) Always Below 1 Ω
      5 (EFI-MAIN NO. 3 relay) - C17-4 (+B) Always Below 1 Ω
      5 (EFI-MAIN NO. 3 relay), C17-1 (+B2) or C17-4 (+B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI-MAIN NO. 1 RELAY - EFI-MAIN NO. 3 RELAY) 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  8. CHECK HARNESS AND CONNECTOR (WATER INLET HOUSING WITH WATER PUMP SUB-ASSEMBLY - ECM) 
    1. Disconnect the water inlet housing with water pump sub-assembly connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C17-5 (NWP) - C34-51 (WPI) Always Below 1 Ω
      C17-5 (NWP) or C34-51 (WPI) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [10/2018 - 07/2022]  Refer to  REMOVAL [07/2022 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR