NAVIGATION SYSTEM, Diagnostic DTC:B15C2

DTC Code DTC Name
B15C2 Speed Signal Malfunction

DESCRIPTION

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

The radio 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 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 assembly. The signal is changed to a pulse signal at the transistor in the combination meter 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 diagram below will not operate normally.

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

  • Radio receiver assembly

  • Combination meter assembly

  • Harness or connector

  • No. 4 Junction connector

WIRING DIAGRAM

B001N6NE05

CAUTION / NOTICE / HINT

Note

Depending on the parts that are replaced during vehicle inspection or maintenance, performing initialization, registration or calibration may be needed. Refer to Precaution for Navigation System Click here.

PROCEDURE


  1. CHECK SYSTEM SENSORS (OPERATION CHECK)


    1. B001MOD

      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 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 RADIO RECEIVER ASSEMBLY Click here

    NG

  2. INSPECT COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM)


    1. B001KCLE01
      Text in Illustration
      *a

      Component with harness connected

      (Combination Meter Assembly)

      Check the output waveform.


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

      2. Connect an oscilloscope to terminal H19-40 (+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 H19-40 (+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 RADIO RECEIVER ASSEMBLY (INPUT WAVEFORM)


    1. B001N2IE01
      Text in Illustration
      *a

      Component with harness connected

      (Radio Receiver Assembly)

      Check the input waveform.


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

      2. Connect an oscilloscope to terminal H147-56 (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 H147-56 (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 RADIO RECEIVER ASSEMBLY Click here

    NG

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


    1. Disconnect the H147 radio receiver assembly connector.

    2. Disconnect the H117 junction connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H147-56 (SPD) - H117-99 Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Disconnect the H19 combination meter assembly connector.

    2. Disconnect the H117 junction connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H19-40 (+S) - H117-59 Always Below 1 Ω

    OK

    REPLACE JUNCTION CONNECTOR

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR