PUSH-BUTTON START, Diagnostic DTC:B2274

DTC Code DTC Name
B2274 ACC Monitor Malfunction

DESCRIPTION

This DTC is stored when a malfunction in the ACC output circuit is detected. The ACC output circuit is the circuit that goes from the ACC output terminal of the certification ECU (smart key ECU assembly) to the ACC relay.

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 No. Detection Item DTC Detection Condition Trouble Area DTC Output from
B2274 ACC Monitor Malfunction

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


  • Malfunction in the ACC relay circuit in the certification ECU (smart key ECU assembly).

  • Malfunction in the external circuit.

Tech Tips

When the voltage at terminal ACCD is not at the standard, the system is determined to be malfunctioning.

  • AM2 fuse

  • RH ACC relay (cowl side junction block RH)

  • Certification ECU (smart key ECU assembly)

  • Wire harness or connector

 Wait 10 seconds after turning the engine switch on (ACC) or on (IG), and then wait another 10 seconds after turning the engine switch off.

DTC Detection Conditions
Vehicle Condition
Pattern 1 Pattern 2
Diagnosis Condition - ○ ○
Malfunction Status Malfunction in the ACC relay circuit in the certification ECU (smart key ECU assembly). ○ -
Malfunction in the external circuit. - ○
Detection Time - -
Number of Trips 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

Vehicle Condition and Fail-safe Function when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Function when Malfunction Detected

  • If there is a malfunction due to the relay being stuck on, the ACC relay does not turn off even though the engine switch is off.

  • If there is a malfunction due to the relay being stuck off, the ACC relay does not turn on even though the engine switch is on (ACC).

    Tech Tips

    The engine switch can be turned on (IG) and the engine can be started.

 -
Related Data List and Active Test Items
DTC Data List Item Active Test Item
B2274

    Power Source Control:

  • ACC Relay Monitor


    Starting Control:

  • Ignition

 -

WIRING DIAGRAM

B002DH2E03

CAUTION / NOTICE / HINT

Note


  • When using the GTS with the engine switch off to troubleshoot:

    Connect the GTS to the DLC3 and turn a courtesy light switch on and off at 1.5 second intervals until communication between the GTS and vehicle begins.

  • The push-button start 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 push-button start after confirming that the communication systems are functioning properly.

  • Before replacing the certification ECU (smart key ECU assembly), refer to the push-button start 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.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (POWER SOURCE)


    1. B002EYSC70
      *a

      Rear view of wire harness connector

      (to Certification ECU (Smart Key ECU Assembly))

      Disconnect the 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
      A21-2 (+B) - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

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

    OK

  2. CHECK HARNESS AND CONNECTOR (GROUND)


    1. B002EYSC71
      *a

      Rear view of wire harness connector

      (to Certification ECU (Smart Key ECU Assembly))

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A21-11 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - COWL SIDE JUNCTION BLOCK RH)


    1. Disconnect the K74 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the 4A cowl side junction block RH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K74-4 (ACCD) - 4A-19 Always Below 1 Ω
      4A-4 - Body ground
      K74-4 (ACCD) or 4A-19 - Body ground 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK COWL SIDE JUNCTION BLOCK RH (ACC RELAY)


    1. Remove the cowl side junction block RH.

      B002DYEC05
      *a

      Component without harness connected

      (Cowl Side Junction Block RH)

      		 - -

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      4E-1 - 4A-45 Battery voltage not applied to terminals 4A-19 and 4A-4 10 kΩ or higher
      Battery voltage applied to terminals 4A-19 and 4A-4 Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE COWL SIDE JUNCTION BLOCK RH

    OK

  5. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. B002EB8C16
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      Reconnect the certification ECU (smart key ECU assembly) connector

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      K74-4 (ACCD) - Body ground Engine switch off → Engine switch on (ACC) 1 V or less → 8.5 V or higher
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)