NAVIGATION SYSTEM Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter
| DTC Code | DTC Name |
|---|---|
| Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter |
DESCRIPTION
The stereo component amplifier assembly receives a vehicle speed signal from the combination meter assembly to control the ASL function.
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 system 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.
WIRING DIAGRAM
for 1ND-TV
for 1NR-FE
for 1ZR-FAE
PROCEDURE
INSPECT COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM)
Check the output waveform.
*a
Component with harness connected
(Combination Meter Assembly)
-
-
Remove the combination meter assembly with the connector still connected.
Connect an oscilloscope to terminal E46-6 (+S) and body ground.
Turn the ignition switch to ON.
Turn a wheel slowly.
Check the signal waveform according to the condition(s) in the table below.
Item
Condition
Measurement terminal
E46-6 (+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.
Tip: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.
Result
Proceed to
OK
NG
INSPECT STEREO COMPONENT AMPLIFIER ASSEMBLY (INPUT WAVEFORM)
Check the input waveform.
*a
Component with harness connected
(Stereo Component Amplifier Assembly)
-
-
Remove the stereo component amplifier assembly with the connector still connected.
Connect an oscilloscope to terminal E92-11 (SPD) and body ground.
Turn the ignition switch to ON.
Turn a wheel slowly.
Check the signal waveform according to the condition(s) in the table below.
Item
Condition
Measurement terminal
E92-11 (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.
Tip: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.
Result
Proceed to
OK
NG
CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER ASSEMBLY - JUNCTION CONNECTOR)
Disconnect the E92 stereo component amplifier assembly connector.
Disconnect the E54 junction connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
E92-11 (SPD) - E54-11
Always
Below 1 Ω
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
CHECK JUNCTION CONNECTOR
Disconnect the E54 junction connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
E54-11 - E54-7
Always
Below 1 Ω
Result
Proceed to
OK
NG
NG REPLACE JUNCTION CONNECTOR
CHECK HARNESS AND CONNECTOR (JUNCTION CONNECTOR - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)
Disconnect the E54 junction connector.
Disconnect the 3D instrument panel junction block assembly connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
E54-7 - 3D-20
Always
Below 1 Ω
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)
Disconnect the E46 combination meter assembly connector.
Disconnect the 3D instrument panel junction block assembly connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
E46-6 (+S) - 3D-38
Always
Below 1 Ω
Result
Proceed to
OK
NG
OK REPAIR OR REPLACE HARNESS OR CONNECTOR