B15C2

NAVIGATION / MULTI INFO DISPLAY: NAVIGATION SYSTEM (w/ USB Audio System): B15C2: Speed Signal Malfunction
B15C2 - Speed Signal Malfunction

DESCRIPTION

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





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK VEHICLE SENSOR (OPERATION CHECK)

(a) Enter the "GPS & Vehicle Sensor" (Vehicle Sensors) Operation Check.





(b) While driving the vehicle, compare the "SPD" indicator to the reading on the speedometer. Check if these readings are equal or almost equal.

OK:

The readings are equal or almost equal.

NG -- GO TO METER / GAUGE SYSTEM How To Proceed With Troubleshooting
OK -- Continue to next step.

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

(a) Disconnect the D55 navigation receiver assembly connector.

(b) Disconnect the D18 combination meter assembly connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. CHECK COMBINATION METER ASSEMBLY (SPEED SIGNAL)

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





(b) Connect an oscilloscope to terminal D18-10 (+S) and body ground.

(c) Turn the ignition switch to ON.

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

Measurement Condition





OK:

The waveform display is as shown in the illustration.

HINT
When the system is function normally, one wheel revolution generates 4 pulses.

As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

Text in Illustration





NG -- REPLACE COMBINATION METER ASSEMBLY Removal

OK -- REPLACE NAVIGATION RECEIVER ASSEMBLY Removal