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HOMESERVICE MANUALSTOYOTA2013TUNDRA BASE, 5.7L ENG VIN WREPAIR AND DIAGNOSISBODY & FRAMEDOOR LOCKSTHEFT DETERRENT SYSTEM (DIAGNOSTICS & CIRCUIT TESTS)THEFT DETERRENT SYSTEMCIRCUIT TESTSECU POWER SOURCE CIRCUITPROCEDURE
2013 Toyota Tundra Base, 5.7L Eng VIN W

ECU Power Source Circuit: Procedure

2013 Toyota Tundra Base, 5.7L Eng VIN WSECTION Procedure
  1. INSPECT FUSE (DR/LCK, ECU-B1) 
    1. Remove the DR/LCK fuse from the main body ECU.
    2. Remove the ECU-B1 fuse from the engine room junction block unit B.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      DR/LCK fuse Always Below 1 Ω
      ECU-B1 fuse

    NG → REPLACE FUSE 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND) 
    Fig 1: Identifying Main Body ECU Connector Terminals
    GTY183479Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the DA, DB and DD main body ECU connectors.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Condition Specified Condition
      DB-13 (BECU) - Body ground Always 11 to 14 V
      DA-1 (ALTB) - Body ground
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      DD-62 (GND1, GND2) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   3 

  3. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE  
RENDER: 1.0x

NO RELATED

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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