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DTC B2271: Ignition Hold Monitor Malfunction: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - POWER MANAGEMENT CONTROL ECU) 
    1. Disconnect the L135 and L136 connectors from the power management control ECU.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      L135-1 (AM22) - Body ground Always 9.5 to 16 V
      L136-7 (AM21) - Body ground Always 9.5 to 16 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - POWER MANAGEMENT CONTROL ECU) 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      L135-5 (E01) - Body ground Always Below 1 Ω
      L135-6 (E1) - Body ground Always Below 1 Ω
      L136-4 (E12) - Body ground Always Below 1 Ω
      L136-5 (E02) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - BODY GROUND) 

    OK: Go to next step 

  3. INSPECT IG2 RELAY 
    1. Remove the engine room relay block assembly.
      Fig 1: Identifying 1A Connector Terminals
      GTY324600Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1A-2 - 1A-3 20°C (68°F) 130 to 230 Ω
      TEXT IN ILLUSTRATION

      *1 Component without harness connected
      (Engine Room Relay Block)

    NG → REPLACE IG2 RELAY 

    OK: Go to next step 

  4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (IG1 NO. 1, IG1 NO. 2 AND IG1 NO. 3 RELAYS) 
    1. Remove the instrument panel junction block assembly.
      Fig 2: Inspecting Instrument Panel Junction Block Assembly Connector Terminals
      GTY323783Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2B-25 - 2B-4 20°C (68°F) 101.25 to 123.75 Ω
      2B-25 - 2B-6 20°C (68°F) 101.25 to 123.75 Ω
      2B-4 - 2B-6 Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Component without harness connected
      (Instrument Panel Junction Block Assembly)

    NG → See step   10 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INSTRUMENT PANEL J/B) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      L136-2 (IG1D) - 2B-25 Always Below 1 Ω
      L136-2 (IG1D) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2B-4 - Body ground Always Below 1 Ω
      2B-6 - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND) 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - IG2 RELAY) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A86-2 (IG2D) - 1A-2 Always Below 1 Ω
      A86-2 (IG2D) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - IG2 RELAY) 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (ENGINE ROOM RELAY BLOCK ASSEMBLY - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1A-3 - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE ROOM RELAY BLOCK ASSEMBLY - BODY GROUND) 

    OK: Go to next step 

  9. CHECK POWER MANAGEMENT CONTROL ECU 
    1. Install the instrument panel junction block assembly.
      Fig 3: Checking Power Management Control ECU Connector Terminals
      GTY333078Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Install the engine room relay block.
    3. Reconnect the A86 and L136 connectors.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A86-2 (IG2D) - Body ground Power switch on (IG) Output voltage at terminal AM21 or AM22 is -2.5 V or more
      L136-2 (IG1D) - Body ground Power switch on (IG) Output voltage at terminal AM21 or AM22 is -2.5 V or more
      TEXT IN ILLUSTRATION

      *1 Component with harness connected
      (Power Management Control ECU)

    NG → See step   11 

    OK → See step   12 

  10. REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL 
  11. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL 
  12. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
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