AUDIO AND VISUAL SYSTEM, Diagnostic DTC:B15C2

DTC Code DTC Name
B15C2 Speed Signal Malfunction

DESCRIPTION

The multi-media module receiver assembly receives a vehicle speed signal from the No. 1 meter ECU sub-assembly and information from the navigation antenna assembly (w/o Manual [SOS] Switch) or telephone antenna assembly (w/ Manual [SOS] Switch), and then adjusts the vehicle position on the map. The multi-media module receiver assembly stores this DTC when the difference between the speed information that the navigation antenna assembly (w/o Manual [SOS] Switch) or telephone antenna assembly (w/ Manual [SOS] Switch) receives and the SPD pulse received from the No. 1 meter ECU sub-assembly becomes large.

Tech Tips


  • A voltage of 12 V or 5 V is output from each ECU and then input to the No. 1 meter ECU sub-assembly. The signal is changed to a pulse signal at the transistor in the No. 1 meter ECU sub-assembly. Each ECU controls the respective systems based on the 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 Code DTC Detection Condition Trouble Area
B15C2 A difference between the GPS speed and SPD pulse is detected

  • No. 1 meter ECU sub-assembly

  • Multi-media module receiver assembly

  • Harness or connector

WIRING DIAGRAM

A01GMWLE22

INSPECTION PROCEDURE

Note

After replacing the multi-media module receiver assembly of vehicles subscribed to pay-type satellite radio broadcasts, XM radio ID registration is necessary (w/ SDARS System).

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Recheck for DTCs and check if the same DTC is output again Click here.

      OK
      No DTCs are output.

    NG

    CHECK VEHICLE SENSOR (OPERATION CHECK) Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  3. CHECK VEHICLE SENSOR (OPERATION CHECK)


    1. A01GKST

      Enter the "Vehicle Sensors" screen. [Refer to Check GPS & Vehicle Sensor in Operation Check Click here]

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

      Tech Tips

      The No. 1 meter ECU 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 "Vehicle Sensors" screen is almost the same as the actual vehicle speed measured using the GTS (See page Click here).

    NG

    CHECK NO. 1 METER ECU ASSEMBLY Click here

    OK

    REPLACE MULTI-MEDIA MODULE RECEIVER ASSEMBLY Click here

  4. CHECK NO. 1 METER ECU ASSEMBLY


    1. A01GJB9E01
      Text in Illustration
      *a

      Component with harness connected

      (No. 1 Meter ECU Sub-assembly)

      Check the output waveform.


      1. Remove the No. 1 meter ECU sub-assembly with the connector still connected.

      2. Connect an oscilloscope to terminal L10-10 (+S) and body ground.

      3. Turn the engine 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 L10-10 (+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

    CHECK HARNESS AND CONNECTOR (MULTI-MEDIA MODULE RECEIVER ASSEMBLY - NO. 1 METER ECU SUB-ASSEMBLY) Click here

    OK

    GO TO METER / GAUGE SYSTEM Click here

  5. CHECK HARNESS AND CONNECTOR (MULTI-MEDIA MODULE RECEIVER ASSEMBLY - NO. 1 METER ECU SUB-ASSEMBLY)


    1. Disconnect the L146 multi-media module receiver assembly connector.

    2. Disconnect the L10 No. 1 meter ECU sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L146-56 (SPD) - L10-10 (+S) Always Below 1 Ω
      L146-56 (SPD) or L10-10 (+S) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MULTI-MEDIA MODULE RECEIVER ASSEMBLY Click here