LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2024 >> RX 500h >> Repair and Diagnosis >> External Pages >> Different car >> Section 148 (Plug-In Charge Control System - Diagnostic Codes (3 Of 3), Symptom Tests & Circuit Tests) >> PLUG-IN CHARGE CONTROL SYSTEM (for PHEV Model) >> ECU Power Source Circuit [08/2023 - ] >> Procedure

ECU Power Source Circuit [08/2023 - ]: Procedure

WARNING: This page is about a different car, the 2025 Lexus RX 450h+ and 2024 Lexus RX 450h+. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK DTC OUTPUT (HEALTH CHECK) 
    1. Enter the following menus: Health Check.
    2. Check DTCs.

      Result

      Result Proceed to
      No DTCs are output A
      DTCs are output B
    3. Turn the ignition switch off.

    Result: 

    B 

    GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2023 - ] 

    Result: 

    A 

    See step  2

  2. CHECK ELECTRIC VEHICLE CHARGER ASSEMBLY (BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Case of electric vehicle charger assembly - Body ground Always Below 1 Ω

      HINT: 

      As the electric vehicle charger assembly is grounded through its case, make sure that the installation bolts of the electric vehicle charger assembly are tightened to the specified torque.

      Refer to INSTALLATION [08/2023 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    TIGHTEN INSTALLATION BOLT. Refer to  INSTALLATION [08/2023 - ] 

    Result: 

    OK 

    See step  3

  3. CHECK ELECTRIC VEHICLE CHARGER ASSEMBLY (AMD2 TERMINAL VOLTAGE) 

    Refer to PROCEDURE - Step 4

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  4

  4. CHECK ELECTRIC VEHICLE CHARGER ASSEMBLY (IGCT VOLTAGE) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the appropriate service information because this may cause a malfunction.

    2. Connect the cable to the negative (-) auxiliary battery terminal.
    3. Disconnect the H124 electric vehicle charger assembly connector.
    4. Turn the ignition switch to ON.
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      H124-5 (IGCT) - Body ground Ignition switch ON 11 to 14 V
    6. Turn the ignition switch off.
    7. Reconnect the electric vehicle charger assembly connector.
    8. Disconnect the cable from the negative (-) auxiliary battery terminal.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO PROBLEM SYMPTOMS TABLE (PLUG-IN CHARGE CONTROL SYSTEM). Refer to  PROBLEM SYMPTOMS TABLE [08/2023 - ] 

    Result: 

    NG 

    See step  6

  5. CHECK FUSE (AMD2) 
    1. Remove the AMD2 fuse from the No. 2 engine room relay block and No. 2 junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      AMD2 fuse terminals Always Below 1 Ω
    3. Install the AMD2 fuse.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (AMD2 FUSE HOLDER - ELECTRIC VEHICLE CHARGER ASSEMBLY) 

    Result: 

    NG 

    See step  9

  6. CHECK FUSE (IGCT NO. 4) 
    1. Remove the IGCT NO. 4 fuse from the No. 1 luggage room relay block and No. 1 junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      IGCT NO. 4 fuse terminals Always Below 1 Ω
    3. Install the IGCT NO. 4 fuse.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  10

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (NO. 1 LUGGAGE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK - ELECTRIC VEHICLE CHARGER ASSEMBLY) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the appropriate service information because this may cause a malfunction.

    2. Remove the IGCT NO. 4 fuse from the No. 1 luggage room relay block and No. 1 junction block assembly.
    3. Disconnect the H124 electric vehicle charger assembly connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H124-5 (IGCT) - IGCT NO. 4 fuse terminal 2 Always Below 1 Ω
    5. Reconnect the electric vehicle charger assembly connector.
    6. Install the IGCT NO. 4 fuse.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. INSPECT RELAY (IGCT SCENE) 

    Refer to ON-VEHICLE INSPECTION [10/2022 - ]

    Result

    Proceed to
    OK
    NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IGCT-SCENE RELAY - IGCT NO. 4 FUSE) 

    Result: 

    NG 

    REPLACE RELAY (IGCT SCENE) 

  9. CHECK HARNESS AND CONNECTOR (NO. 2 ENGINE ROOM RELAY BLOCK AND NO. 2 JUNCTION BLOCK ASSEMBLY - ELECTRIC VEHICLE CHARGER ASSEMBLY) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the appropriate service information because this may cause a malfunction.

    2. Remove the AMD2 fuse from the No. 2 engine room relay block and No. 2 junction block assembly.
    3. Disconnect the H125 electric vehicle charger assembly connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H125-1 (AMD2) or AMD2 fuse terminal 2 - Body ground and other terminals Always 10 kΩ or higher
    5. Reconnect the electric vehicle charger assembly connector.
    6. Install the AMD fuse.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FUSE (AMD2) 

    Result: 

    NG 

    See step  11

  10. CHECK HARNESS AND CONNECTOR (NO. 1 LUGGAGE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY - ELECTRIC VEHICLE CHARGER ASSEMBLY) 
    WARNING:

    Be sure to wear insulated gloves.

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the appropriate service information because this may cause a malfunction.

    2. Disconnect the H124 electric vehicle charger assembly connector.
    3. Disconnect the C35 transmission floor shift assembly (shift control ECU) connector.
    4. Disconnect the B56 shift control actuator assembly (shift actuator ECU) connector.
    5. Disconnect the H58 voltage inverter assembly connector. (w/ voltage inverter assembly)
    6. Remove the IGCT NO. 4 fuse from the No. 1 luggage room relay block and No. 1 junction block assembly.
    7. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H124-5 (IGCT) or IGCT NO. 4 fuse terminal 2 - Body ground and other terminals Always 10 kΩ or higher
    8. Reconnect the voltage inverter assembly connector. (w/ voltage inverter assembly)
    9. Reconnect the shift control actuator assembly (shift actuator ECU) connector.
    10. Reconnect the transmission floor shift assembly (shift control ECU) connector.
    11. Reconnect the electric vehicle charger assembly connector.
    12. Install the IGCT NO. 4 fuse.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FUSE (IGCT NO. 4) 

    Result: 

    NG 

    See step  12

  11. REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    REPLACE FUSE (AMD2) 

  12. REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    REPLACE FUSE (IGCT NO. 4) 

scientia non olet · About LEMON Manuals