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Home >> Toyota >> 2012 >> Prius Three >> Repair and Diagnosis (Single Page) >> External Pages >> Different variant/trim >> Section 10 (Theft Deterrent / Keyless Entry System (Diagnostics & Service Information) (Plug-In)) >> Push-Button Start >> Symptom Tests >> Power Source Mode does not Change to ON (ACC) >> Procedure
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Power Source Mode does not Change to ON (ACC): Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK HARNESS OR 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 OR 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 See step   3 

    NG → See step   7 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INSTRUMENT PANEL J/B) See step   4 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND) See step   5 

    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 See step   6 

    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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