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DTC B2274: ACC Monitor Malfunction: Procedure

  1. CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - POWER MANAGEMENT CONTROL ECU) See step   1 

    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) See step   2 

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

    OK: Go to next step 

  3. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Remove the instrument panel junction block assembly.
      Fig 1: Inspecting Instrument Panel Junction Block Assembly
      GTY227553Courtesy 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
      2A-43 - 2B-4 20°C (68°F) 101.25 to 123.75 Ω
      2A-43 - 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   7 

    OK: Go to next step 

  4. 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
      L6-1 (ACCD) - 2A-43 Always Below 1 Ω
      L6-1 (ACCD) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

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

  6. INSPECT POWER MANAGEMENT CONTROL ECU 
    1. Reinstall the instrument panel junction block assembly.
      Fig 2: Inspecting Power Management Control ECU
      GTY211856Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Reconnect the L5 and L6 connectors.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      L6-1 (ACCD) - Body ground Power switch on (ACC) 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   8 

    OK → See step   9 

  7. REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL 
  8. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL 
  9. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
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