ENTRY AND START SYSTEM(for Start Function) Power Source Mode does not Change to ON (ACC)

DESCRIPTION

When the electrical key transmitter is in the vehicle and the engine switch is pressed, the certification ECU (smart key ECU assembly) receives a signal and changes the power source mode. Use this troubleshooting procedure when the power source mode does not change to on (ACC) but does change to on (IG).

Tech Tips

When the battery cable is disconnected and reconnected, the power source mode returns to the mode it was in before the battery cable was disconnected.

WIRING DIAGRAM

A005KRNE05

CAUTION / NOTICE / HINT

Note


  • When using the intelligent tester with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the intelligent tester and vehicle begins, or 2) connect the intelligent tester to the vehicle and select "Manual" from the initial screen on the intelligent tester. Select "KEY REGIST" under Model Code.

  • Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart Click here.

  • The entry and start system uses multiplex communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting Click here.

  • If the entry and start system is disabled through the customize function, enable the system before performing troubleshooting Click here.

  • Inspect the fuses of circuits related to this system before performing the following inspection procedure.

  • After completing repairs, confirm that the problem does not reoccur.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - CERTIFICATION ECU)


    1. Disconnect the F63 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the 3B instrument panel junction block assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      F63-4 (ACCD) - 3B-37 Always Below 1 Ω
      3B-8 - Body ground Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F63-4 (ACCD) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (ACC RELAY)


    1. Remove the instrument panel junction block assembly Click here.

    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

    3. Measure the resistance according to the value(s) in the table below.

      A005HIAE01
      Text in Illustration
      *A for LHD *B for RHD
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -
      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      3E-1 - MB-29 When battery voltage absent 10 kΩ or higher
      When battery voltage is applied to terminals 3B-37 and 3B-8 Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      3F-1 - MB-29 When battery voltage absent 10 kΩ or higher
      When battery voltage is applied to terminals 3B-37 and 3B-8 Below 1 Ω

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    OK

  3. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. Install the main body ECU (multiplex network body ECU) to the instrument panel junction block assembly Click here.

    2. Install the instrument panel junction block assembly.

    3. A005HXCE01
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      Reconnect the F63 certification ECU (smart key ECU assembly) connector.

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      F63-4 (ACCD) - Body ground Engine switch off 1 V or less
      Engine switch on (ACC) 8.5 V or higher

    OK

    CHECK RELAY CONTACT SIDE CIRCUIT

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)