Vehicle Speed Signal Circuit between Radio Receiver and Combination Meter [10/2015 - ]: Procedure
- CHECK VEHICLE SIGNAL (OPERATION CHECK)
- Enter the "Vehicle Signal Check Mode" screen. Refer to Check Vehicle Signal in Operation Check (Refer to OPERATION CHECK [10/2015 - ]
).
- While driving the vehicle, compare the value displayed for "SPEED" to the reading on the speedometer. Check if these readings are almost equal.
HINT:
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 in 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 Signal Check Mode" screen is almost the same as the actual vehicle speed measured using the Techstream (Refer to DATA LIST / ACTIVE TEST [10/2015 - ] ).
Result:
OK
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE
(Refer to PROBLEM SYMPTOMS TABLE [10/2015 - ] )
Result:
NG
See step 2
- Enter the "Vehicle Signal Check Mode" screen. Refer to Check Vehicle Signal in Operation Check (Refer to OPERATION CHECK [10/2015 - ]
).
- INSPECT COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM)
- Check the output waveform.TEXT IN ILLUSTRATION
*a Component with harness connected
(Combination Meter Assembly)- - - Remove the combination meter assembly with the connector still connected.
- Connect an oscilloscope to terminal D9-9 (+S) and body ground.
- Turn the power switch on (IG).
- Turn a wheel slowly.
- Check the signal waveform according to the condition(s) in the table below.
Item Condition Measurement terminal D9-9 (+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.
Result:
NG
GO TO METER / GAUGE SYSTEM
(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ] )
Result:
OK
See step 3
- Check the output waveform.
- INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY (INPUT WAVEFORM)
- Check the input waveform.TEXT IN ILLUSTRATION
*a Component with harness connected
(Radio and Display Receiver Assembly)- - - Remove the radio and display receiver assembly with the connector still connected.
- Connect an oscilloscope to terminal E5-17 (SPD) and body ground.
- Turn the power switch on (IG).
- Turn a wheel slowly.
- Check the signal waveform according to the condition(s) in the table below.
Item Condition Measurement terminal E5-17 (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.
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.
Result:
OK
REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY
(Refer to REMOVAL [10/2014 - ] )
Result:
NG
See step 4
- Check the input waveform.
- CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - NO. 6 JUNCTION CONNECTOR)
- Disconnect the E5 radio and display receiver assembly connector.
- Disconnect the D100 No. 6 junction connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition E5-17 (SPD) - D100-9 Always Below 1 Ω
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 5
- CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - NO. 6 JUNCTION CONNECTOR)
- Disconnect the D9 combination meter assembly connector.
- Disconnect the D100 No. 6 junction connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition D9-9 (+S) - D100-1 Always Below 1 Ω
Result:
OK
REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 6 JUNCTION CONNECTOR)
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR