STEERING LOCK SYSTEM, Diagnostic DTC:B2788

DTC Code DTC Name
B2788 IG2 Signal Malfunction

DESCRIPTION

The steering lock ECU determines the ON / OFF status of the power switch through the IG2 signal circuit.

After receiving an ignition relay No. 2 (IG2) ON signal, the steering lock ECU determines that the vehicle is moving.

The steering lock ECU does not lock the steering when it receives the ignition relay No. 2 (IG2) ON signal. This prevents the steering from being locked while the vehicle is moving.

The diagnosis information of the steering lock ECU is transmitted to the tester via the certification ECU as the steering lock ECU is not connected to the CAN communication system.

DTC Code Detection Condition Trouble Area
B2788 Open or short in IG2 signal circuit

  • Steering lock actuator assembly (steering lock ECU)

  • Ignition relay No. 2 (IG2)

  • Main body ECU

  • Wire harness or connector

WIRING DIAGRAM

A000ZUHE05
*a from Battery
*b Steering Lock Motor
*c Main Body ECU (Driver Side Junction Block Assembly)
*d Steering Lock Actuator Assembly (Steering Lock ECU)

CAUTION / NOTICE / HINT

Tech Tips

When the power switch is OFF, the main body ECU may occasionally go into a non-active state called sleep mode. Therefore, before proceeding with the inspection, it is necessary to perform the following steps to wake up the ECU:

With the power switch OFF, open the driver door. Then (with the power switch still OFF) open and close any door several times at 1.5 second intervals.

PROCEDURE


  1. INSPECT STEERING LOCK ECU

    A000YORE02
    *1 Component with harness connected: (Steering Lock ECU)

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

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      L33-6 (IG2) - L33-1 (GND) Power switch OFF Below 1 V
      L33-6 (IG2) - L33-1 (GND) Power switch ON (IG) 11 to 14 V

    OK

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) Click here

    NG

  2. INSPECT FUSE (ECU-IG, P IG2)


    1. Remove the ECU-IG fuse from the engine room No. 2 junction block.

    2. Remove the P IG2 fuse from the passenger side junction block.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      ECU-IG fuse Always Below 1 Ω
      P IG2 fuse Always Below 1 Ω

    NG

    REPLACE FUSE

    OK

  3. INSPECT IGNITION RELAY NO. 2 (IG2)

    A000UE5E06
    *a Ignition Relay No. 2 (IG2)

    1. Remove the ignition relay No. 2 (IG2) from the engine room No. 2 junction block.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      3 - 5 When battery voltage is applied to terminals 1 and 2 Below 1 Ω
      3 - 5 When battery voltage is not applied to terminals 1 and 2 10 kΩ or higher

    NG

    REPLACE RELAY

    OK

  4. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - IGNITION RELAY NO. 2 (IG2) AND BODY GROUND)

    A000ZTUE02
    *1 Front view of wire harness connector: (to Steering Lock ECU)
    *2 Engine Room No. 2 Junction Block
    *3 Ignition Relay No. 2 (IG2)

    1. Disconnect the L33 steering lock ECU connector.

    2. Remove the ignition relay No. 2 (IG2) from the engine room No. 2 junction block.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      Ignition relay No. 2 (IG2) relay terminal 5 - Body ground Always 11 to 14 V
      Standard resistance
      Tester Connection Condition Specified Condition
      L33-6 (IG2) - Ignition relay No. 2 (IG2) relay terminal 3 Always Below 1 Ω
      L33-6 (IG2) or ignition relay No. 2 (IG2) relay terminal 3 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - IGNITION RELAY NO. 2 (IG2) AND BODY GROUND)

    A000UGOE04
    *1 Front view of wire harness connector: (to Main Body ECU)
    *2 Engine Room No. 2 Junction Block
    *3 Ignition Relay No. 2 (IG2)

    1. Disconnect the L12 main body ECU connector.

    2. Remove the ignition relay No. 2 (IG2) from the engine room No. 2 junction block.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      L12-11 (IG2D) - Ignition relay No. 2 (IG2) relay terminal 1 Always Below 1 Ω
      Ignition relay No. 2 (IG2) relay terminal 2 - Body ground Always Below 1 Ω
      L12-11 (IG2D) or ignition relay No. 2 (IG2) relay terminal 1 - Body ground Always 10 kΩ or higher

    OK

    REPLACE MAIN BODY ECU

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR