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Home >> Toyota >> 2012 >> 4Runner Trail >> Repair and Diagnosis (Single Page) >> Electrical >> Starter >> Smart Key System (For Start Function) (Diagnostic Codes & Symptom Tests) >> SMART KEY SYSTEM (for Start Function) >> Symptom Tests >> Power Source Mode does not Change to ON (IG) >> Procedure
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Power Source Mode does not Change to ON (IG): Procedure

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    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 

    OK: Go to next step 

  3. INSPECT NO. 1 INTEGRATION RELAY (IG2 RELAY) See step   3 

    NG → REPLACE NO. 1 INTEGRATION RELAY 

    OK: Go to next step 

  4. INSPECT DRIVER SIDE JUNCTION BLOCK ASSEMBLY (IG1 NO. 1, IG1 NO. 2 AND IG1 NO. 3 RELAYS) See step   4 

    NG → REPLACE MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY) 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - DRIVER SIDE JUNCTION BLOCK ASSEMBLY) See step   5 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (DRIVER SIDE JUNCTION BLOCK ASSEMBLY - BODY GROUND) See step   6 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - NO. 1 INTEGRATION RELAY) See step   7 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - BODY GROUND) See step   8 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. CHECK POWER MANAGEMENT CONTROL ECU See step   9 

    NG → See step   11 

    OK: Go to next step 

  10. CONFIRM TEST See step   6 

    NG → CHECK RELAY CONTACT SIDE CIRCUIT 

    OK → See step   12 

  11. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL 
  12. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING