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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. Refer to REMOVAL - Step 3 .
      Fig 1: Identifying 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
      F52-19 (ACCD) - 2A-43 Always Below 1 Ω
      F52-19 (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: Identifying F52 Connector Terminal
      GTY283250Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Reconnect the F52 connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      F52-19 (ACCD) - Body ground Power switch on (ACC) Output voltage at terminal AM21 or AM22 is -2 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 - Step 3 
  8. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL 
  9. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING