NAVIGATION SYSTEM(for Navigation Receiver Type), Diagnostic DTC:B15C2

DTC Code DTC Name
B15C2 Speed Signal Malfunction

DESCRIPTION

The navigation receiver assembly receives a vehicle speed signal from the combination meter sub-assembly and information from the navigation antenna assembly, and then adjusts the vehicle position.

The navigation receiver assembly stores this DTC when the difference between the speed information that the navigation antenna assembly and the SPD pulse received from the combination meter sub-assembly becomes large.

Tech Tips


  • A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter sub-assembly. The signal is changed to a pulse signal at the transistor in the combination meter sub-assembly. Each ECU controls its respective systems based on this pulse signal.

  • If a short occurs in any of the ECUs or in the wire harness connected to an ECU, all systems in the following diagram will not operate normally.

DTC No. DTC Detection Condition Trouble Area
B15C2 A difference between the GPS speed and SPD pulse is detected

  • Navigation receiver assembly

  • Combination meter sub-assembly

  • Harness or connector

  • Junction connector

WIRING DIAGRAM

A005DK6E01

PROCEDURE


  1. CHECK SYSTEM SENSORS (OPERATION CHECK)


    1. A005CLB

      Enter the "System Sensors Check" screen.

      Refer to Check System Sensors in Operation Check Click here.

    2. While driving the vehicle, compare the value of "Speed" to the reading on the speedometer. Check if these readings are almost equal.

      Tech Tips

      The combination meter sub-assembly receives the vehicle speed signal from the skid control ECU via CAN communication. Therefore, perform the following inspection referring to values on the Data List of the skid control ECU because it is the source of the vehicle speed signal.

      OK
      Vehicle speed displayed on the "System Sensors Check" screen is almost the same as the actual vehicle speed measured using the GTS (See page Click here).

    OK

    REPLACE NAVIGATION RECEIVER ASSEMBLY Click here

    NG

  2. INSPECT COMBINATION METER SUB-ASSEMBLY (OUTPUT WAVEFORM)


    1. A005B5WE01
      Text in Illustration
      *a

      Component with harness connected

      (Combination Meter Sub-assembly)

      Check the output waveform.


      1. Remove the combination meter sub-assembly with the connector(s) still connected.

      2. Connect an oscilloscope to terminal L27-15 (+S) and body ground.

      3. Turn the power switch on (IG).

      4. Turn a wheel slowly.

      5. Check the signal waveform according to the condition(s) in the table below.

        Item Condition
        Measurement terminal L27-15 (+S) - Body ground
        Tool setting 5 V/DIV., 20 ms./DIV.
        Vehicle condition Wheel being rotated
        OK
        The waveform is similar to that shown in the illustration.

        Tech Tips

        When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.


    NG

    GO TO METER / GAUGE SYSTEM Click here

    OK

  3. INSPECT NAVIGATION RECEIVER ASSEMBLY (INPUT WAVEFORM)


    1. A005AICE01
      Text in Illustration
      *a

      Component with harness connected

      (Navigation Receiver Assembly)

      Check the input waveform.


      1. Remove the navigation receiver assembly with the connector(s) still connected.

      2. Connect an oscilloscope to terminal L38-17 (SPD) and body ground.

      3. Turn the power switch on (IG).

      4. Turn a wheel slowly.

      5. Check the signal waveform according to the condition(s) in the table below.

        Item Condition
        Measurement terminal L38-17 (SPD) - Body ground
        Tool setting 5 V/DIV., 20 ms./DIV.
        Vehicle condition Wheel being rotated
        OK
        The waveform is similar to that shown in the illustration.

        Tech Tips

        When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.


    OK

    REPLACE NAVIGATION RECEIVER ASSEMBLY Click here

    NG

  4. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - JUNCTION CONNECTOR)


    1. Disconnect the L38 navigation receiver assembly connector.

    2. Disconnect the L70 junction connector.

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

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      L38-17 (SPD) - L70-3 Always Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      L38-17 (SPD) - L70-12 Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (COMBINATION METER SUB-ASSEMBLY - JUNCTION CONNECTOR)


    1. Disconnect the L27 combination meter sub-assembly connector.

    2. Disconnect the L70 junction connector.

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

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      L27-15 (+S) - L70-32 Always Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      L27-15 (+S) - L70-31 Always Below 1 Ω

    OK

    REPLACE JUNCTION CONNECTOR

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR