STEERING LOCK SYSTEM, Diagnostic DTC:B2781

DTC Code DTC Name
B2781 Open / Short in Steering Lock ECU

DESCRIPTION

The steering lock ECU and steering lock motor are built into the steering lock actuator assembly.

The steering lock ECU detects whether the steering lock is in the lock or unlock position by using the lock position sensor of the steering lock motor.

The steering lock ECU receives lock and unlock request signals from the certification ECU (smart key ECU assembly) and responds with lock and unlock operation signals.

Tip:

The steering lock ECU is not connected to the CAN communication system. However, the steering lock ECU is connected to the certification ECU (smart key ECU assembly) via LIN communication and communicates with other components via CAN communication through the certification ECU (smart key ECU assembly).

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B2781

Open / Short in Steering Lock ECU

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

  • The steering lock/unlock position sensor is malfunctioning.*2

  • The steering lock motor activation circuit has a short circuit.

  • The steering lock motor activation circuit has an open circuit.

  • Steering lock ECU (Steering lock actuator assembly)

  • LIN communication system

No confirmation operation is necessary (monitoring is continuous).

  • *1: Only output while a malfunction is present and the engine switch is on (IG).

  • *2: When both detection switches turn on, the system is determined to be malfunctioning.

C221981E10
Table 1. Vehicle Condition and Fail-safe Function when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Function when Malfunction Detected

The steering cannot be locked or unlocked. For this reason, the engine cannot be started.

Prohibits the engine from being started (the engine does not crank).
Table 2. Related Data List and Active Test Items

DTC No.

Data List Item

Active Test Item

B2781

  • Entry&Start

  • Sensor Value

  • Motor Driver Short

-

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.

  • After performing repairs, confirm that no DTCs are output again.

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  • When replacing the steering lock ECU (steering lock actuator assembly), registration must be performed (Refer to the Service Bulletin).

Tip:

When all the ECUs that are connected to the LIN communication cannot communicate with the certification ECU (smart key ECU assembly), DTC B2785 is stored.

PROCEDURE

  1. CHECK DTC

    1. Using the GTS, check if LIN communication DTC B2785 is output.

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      Tip:

      If a LIN communication DTC is output, perform troubleshooting for the LIN communication system.

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      Result

      Proceed to

      DTC B2785 is output.

      DTC B2785 is not output.
    DTC B2785 is output.

    GO TO LIN COMMUNICATION SYSTEM (DTC B2785)

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    DTC B2785 is not output.

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

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