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

DESCRIPTION

When the key is in the vehicle and the power 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 certification ECU (smart key ECU assembly) is replaced with a new one and the cable is connected to the negative (-) auxiliary battery terminal, the power source mode changes to on (IG).

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

WIRING DIAGRAM

B005YMVE22
B005YMVE24

CAUTION / NOTICE / HINT

Note


  • 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 for circuits related to this system before performing the following inspection procedure.

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

Tech Tips

Related Data List and Active Test Items
Problem Symptom Data List Item Active Test Item
Power source mode does not change to on (ACC) but does change to on (IG)

    Power Source Control

  • Power Supply Condition

  • ACC Relay Monitor

 -

PROCEDURE


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


    1. Disconnect the L197 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the 2A and 2B instrument panel junction block assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L197-4 (ACCD) - 2A-25 Always Below 1 Ω
      2B-9 - Body ground Always Below 1 Ω
      L197-4 (ACCD) or 2A-25 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      B005XROE02
      Text in Illustration
      *A for LHD *B for RHD
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

    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) the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition

      2E-1 - 2B-13*1

      2F-1 - 2B-13*2

      		 Auxiliary battery voltage not applied between terminals 2A-25 and 2B-9 10 kΩ or higher
      Auxiliary battery voltage applied between terminals 2A-25 and 2B-9 Below 1 Ω

      • *1: for LHD

      • *2: for RHD


    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    OK

  3. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. B005ZRJE02
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      Reconnect the L197 certification ECU (smart key ECU assembly) connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      L197-4 (ACCD) - Body ground Power switch off → Power switch on (ACC)) 1 V or less → 8.5 V or higher

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)