SMART ENTRY AND START SYSTEM (for Start Function), Diagnostic DTC:B2271

DTC Code DTC Name
B2271 Ignition Hold Monitor Malfunction

DESCRIPTION

This DTC is stored when a malfunction in the IG circuit or IG hold circuit in the certification ECU (smart key ECU assembly) is detected.

Tech Tips

When the cable is disconnected and reconnected to the negative (-) battery terminal, the power source mode returns to the state it was in before the cable was disconnected.

DTC Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2271

When either of the following conditions is met (1-trip detection logic*):


  • The IG circuit in the certification ECU (smart key ECU assembly) is malfunctioning.

  • The IG hold circuit in the certification ECU (smart key ECU assembly) is malfunctioning.

  • AM2 fuse

  • Certification ECU (smart key ECU assembly)

  • Wire harness or connector

 IG ON

Tech Tips


  • The IG circuits activate the IG relays.

  • After the IG circuits turn on, even if the CPU operates incorrectly, the IG hold circuit maintains the power source mode in on (IG).

Vehicle Condition and Fail-safe Function when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Function when Malfunction Detected
The engine switch cannot be turned on (IG) (the engine cannot be started). The power source mode cannot be changed to on (IG).

WIRING DIAGRAM

A003BTIE01

INSPECTION PROCEDURE

Note


  • When using the GTS with the vehicle engine switch off, connect the GTS to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select the Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry & Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

  • The smart entry and start system (for Start Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting Click here. Troubleshoot the smart entry and start system (for Start Function) after confirming that the communication systems are functioning properly.

  • Before replacing the certification ECU (smart key ECU assembly), refer to the smart entry and start system (for Start Function) precaution Click here.

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

  • After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

Tech Tips

Related Data List and Active Test Items
DTC Data List Item Active Test Item
B2271

    Power Source Control

  • IG Relay Monitor (Inside)

  • Latch Circuit


    Starting Control

  • Ignition

 -

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (POWER SOURCE)


    1. Disconnect the B75 certification ECU (smart key ECU assembly) connector.

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

      A003H7QE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Certification ECU (Smart Key ECU Assembly))

      		 - -
      Standard Voltage
      Tester Connection Condition Specified Condition
      B75-1 (+B) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE

    OK

  2. CHECK HARNESS AND CONNECTOR (GROUND)


    1. Disconnect the B75 certification ECU (smart key ECU assembly) connector.

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

      A003H7QE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Certification ECU (Smart Key ECU Assembly))

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      B75-10 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. Reconnect the B75 certification ECU (smart key ECU assembly) connector.

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

      A003HSFE01
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      		 - -
      Standard Voltage
      Tester Connection Condition Specified Condition
      B75-20 (IG1D) - Body ground Engine switch on (ACC) → Engine switch on (IG) 1 V or less → 9 V or higher

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    USE SIMULATION METHOD TO CHECK Click here