Dtc B15C2 Speed Signal Malfunction


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK VEHICLE SENSOR (OPERATION CHECK)

CHECK COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM)

CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - COMBINATION METER ASSEMBLY)

DTC B15C2 Speed Signal Malfunction


DESCRIPTION

The navigation 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 navigation receiver assembly stores this DTC when the difference between the speed information that the navigation antenna assembly receives and the SPD pulse received from the combination meter assembly becomes large.
HINT:
  1. 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 the respective systems based on the pulse signal.
  2. 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.
  1. Meter/gauge system
  2. Harness or connector
  3. Navigation receiver assembly

WIRING DIAGRAM


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Navigation Multi Info Display.Navigation System (For Radio And Display Type). Dtc B15C2 Speed Signal Malfunction


INSPECTION PROCEDURE

1.CHECK VEHICLE SENSOR (OPERATION CHECK)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155

  1. Enter the "System Sensors Check" screen. Refer to Check GPS & Vehicle Sensors in Operation Check (LandCruiser RM000003SKF0LEX.html).

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

    OK:
    The readings are equal or almost equal.


NG
Go to step 2
OK

REPLACE NAVIGATION RECEIVER ASSEMBLY (LandCruiser RM000003B6H02GX.html)

2.CHECK COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Navigation Multi Info Display.Navigation System (For Radio And Display Type). Dtc B15C2 Speed Signal Malfunction

  1. Check the output waveform.

    1. Remove the combination meter assembly with the connector(s) still connected (LandCruiser RM000003QKY01CX.html).

    2. Connect an oscilloscope to terminal G6-32 (+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
      		G6-32 (+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.
      HINT:
      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.
      Text in Illustration
      *a
      		Component with harness connected
      (Combination Meter Assembly)


NG
GO TO METER / GAUGE SYSTEM (LandCruiser RM000002Z4L055X.html)
OK


3.CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - COMBINATION METER ASSEMBLY)

  1. Disconnect the H56 navigation receiver assembly connector.

  1. Disconnect the G6 combination meter assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    H56-17 (SPD) - G6-32 (+S)
    		Always
    		Below 1 Ω
    H56-17 (SPD) - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE NAVIGATION RECEIVER ASSEMBLY (LandCruiser RM000003B6H02GX.html)