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Component Tests and General Diagnostics





METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: Speed Signal Circuit
- Speed Signal Circuit

DESCRIPTION

The vehicle speed signal consists of pulses sent to the combination meter assembly from the master cylinder solenoid or brake actuator assembly (skid control ECU).

WIRING DIAGRAM









INSPECTION PROCEDURE

PROCEDURE

1. CHECK ECU TERMINAL VOLTAGE (INPUT VOLTAGE)

(a) Disconnect the G3 meter connector.





(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





Text in Illustration





NG -- CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - NO. 3 JUNCTION BLOCK)
OK -- Continue to next step.

2. CHECK COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE)

(a) Disconnect the A7 master cylinder solenoid (skid control ECU) connector.





(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





Text in Illustration





NG -- CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - SKID CONTROL ECU)
OK -- Continue to next step.

3. CHECK COMBINATION METER ASSEMBLY (SPEED SIGNAL)

(a) Check the input waveform.





(1) Reconnect the G3 meter connector.

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

(3) Connect an oscilloscope to terminal G3-33 (SI) and body ground.

(4) Turn the engine switch on (IG).

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

Measurement Condition





OK:

The waveform displayed is as 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.

NG -- REPLACE MASTER CYLINDER SOLENOID (SKID CONTROL ECU) Disassembly

OK -- REPLACE COMBINATION METER ASSEMBLY Removal

4. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - SKID CONTROL ECU)

(a) Disconnect the G3 meter connector.

(b) Disconnect the A7 master cylinder solenoid (skid control ECU) connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE COMBINATION METER ASSEMBLY Removal

5. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - NO. 3 JUNCTION BLOCK)

(a) Disconnect the G3 meter connector.

(b) Disconnect the 3A junction block 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.

6. CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK)

(a) Inspect for a short in the circuit that is connected to the junction block connector shown in the wiring diagram.

HINT
If the voltage is not as specified, it is possible that an ECU or circuit has a malfunction. The malfunctioning ECU or circuit will be diagnosed in the following steps.

(1) Disconnect the 3C junction block connector.





Text in Illustration





(2) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





*: for 14 Speakers

Result





B -- REPLACE NO. 3 JUNCTION BLOCK
A -- Continue to next step.

7. SYSTEM CHECK

(a) Select the circuit for which the voltage was not as specified in the previous step.

Result





*1: for 14 Speakers

*2: for 9 Speakers

*3: w/ Navigation System

*4: w/ Safety Connect System

*5: w/ Voltage Inverter for 400W Type

D -- CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - NO. 4 JUNCTION BLOCK)

C -- CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - JUNCTION CONNECTOR)

B -- CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - STEREO COMPONENT AMPLIFIER ASSEMBLY)
A -- Continue to next step.

8. CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - WINDSHIELD WIPER SWITCH ASSEMBLY)

(a) Disconnect the G50 windshield wiper switch connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE WINDSHIELD WIPER SWITCH ASSEMBLY Removal

9. CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - STEREO COMPONENT AMPLIFIER ASSEMBLY)

(a) Disconnect the R34 stereo component amplifier connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY Removal

10. CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - JUNCTION CONNECTOR)

(a) Disconnect the 3A junction block connector.

(b) Disconnect the H22 junction 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.

11. CHECK HARNESS AND CONNECTOR (JUNCTION CONNECTOR)

(a) Inspect for a short in the circuit that is connected to the junction connector shown in the wiring diagram.

(1) Disconnect the H23 junction block connector.





Text in Illustration





(2) Measure the voltage according to the value(s) in the table below

Standard Voltage:





Result





C -- REPLACE JUNCTION CONNECTOR

B -- CHECK HARNESS AND CONNECTOR (JUNCTION CONNECTOR - STEREO COMPONENT AMPLIFIER ASSEMBLY)
A -- Continue to next step.

12. CHECK HARNESS AND CONNECTOR (JUNCTION CONNECTOR - RADIO RECEIVER ASSEMBLY)

NOTICE:
For vehicles with a navigation system, proceed to next step.

(a) Disconnect the H30 radio receiver connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE RADIO RECEIVER ASSEMBLY Removal

13. CHECK HARNESS AND CONNECTOR (JUNCTION CONNECTOR - DISPLAY AND NAVIGATION MODULE DISPLAY)

(a) Disconnect the H4 display and navigation module display connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY Removal

14. CHECK HARNESS AND CONNECTOR (JUNCTION CONNECTOR - STEREO COMPONENT AMPLIFIER ASSEMBLY)

(a) Disconnect the H10*1 or H25*2 stereo component amplifier assembly connector.

*1: w/ Navigation System

*2: w/o Navigation System

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

Standard Resistance:

w/ Navigation System





w/o Navigation System





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY Removal

15. CHECK HARNESS AND CONNECTOR (NO. 3 JUNCTION BLOCK - NO. 4 JUNCTION BLOCK)

(a) Disconnect the 3A junction block connector.

(b) Disconnect the 4A junction block 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.

16. CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK)

(a) Inspect for a short in the circuit that is connected to the junction connector shown in the wiring diagram.

(1) Disconnect the 4A junction block connector.

(2) Disconnect the 4B junction block connector.





Text in Illustration





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

Standard Voltage:





*1: w/ Safety Connect System
*2: w/ Voltage Inverter for 400 W Type

Result





D -- REPLACE NO. 4 JUNCTION BLOCK

C -- CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - ECM)

B -- CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - VOLTAGE INVERTER)
A -- Continue to next step.

17. SYSTEM CHECK

(a) Select the circuit for which the voltage was not as specified in the previous step.

Result





*: w/ Safety Connect System

C -- CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - TIRE PRESSURE MONITOR ECU)

B -- CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - TELEMATICS TRANSCEIVER)
A -- Continue to next step.

18. CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - POWER MANAGEMENT CONTROL ECU)

(a) Disconnect the G39 power management control ECU connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

19. CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - TELEMATICS TRANSCEIVER)

(a) Disconnect the G56 telematics transceiver connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE TELEMATICS TRANSCEIVER

20. CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - TIRE PRESSURE MONITOR ECU)

(a) Disconnect the R2 tire pressure monitor ECU connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE TIRE PRESSURE MONITOR ECU

21. CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - VOLTAGE INVERTER)

(a) Disconnect the Q19 voltage inverter connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE VOLTAGE INVERTER ASSEMBLY Removal

22. CHECK HARNESS AND CONNECTOR (NO. 4 JUNCTION BLOCK - ECM)

(a) Disconnect the G44 ECM connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ECM Removal
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