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 IG1 circuit, IG2 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 IG1 or IG2 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

Turn the engine switch on (IG).

Tech Tips

To turn the engine switch on (IG), carry the key and press the engine switch twice with the shift lever in P and the brake pedal released.

Tech Tips


  • The IG1 and IG2 circuits activate the IG1 and IG2 relays.

  • After the IG1 and IG2 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

B000MVME05

INSPECTION PROCEDURE

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, select the vehicle type under manual mode, and then enter the following menus: Body / Entry & Start / DTC.

  • 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

  • IG1 Relay Monitor (Inside)

  • IG2 Relay Monitor (Inside)

  • Latch Circuit


    Starting Control

  • Ignition

 -

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (POWER SOURCE)

    B000J85E07
    Text in Illustration
    *a

    Rear view of wire harness connector

    (to Certification ECU (smart key ECU assembly))

    1. Disconnect the A43 connector from the certification ECU (smart key ECU assembly).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A43-2 (+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)

    B000J85E08
    Text in Illustration
    *a

    Rear view of wire harness connector

    (to Certification ECU (smart key ECU assembly))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A43-11 (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 certification ECU (smart key ECU assembly) connector.

      B000KYQE08
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      		 - -

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A43-9 (IG2D) - Body ground Engine switch on (ACC) → Engine switch on (IG) 1 V or less → 9 V or higher
      I78-6 (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