Last Modified: 01-30-2024 6.11:8.1.0 Doc ID: RM100000001KJTV
Model Year Start: 2020 Model: RAV4 Prod Date Range: [10/2019 - 08/2020]
Title: METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: Speed Signal Circuit; 2020 MY RAV4 RAV4 HV [10/2019 - 08/2020]

Speed Signal Circuit

DESCRIPTION

The combination meter assembly receives the vehicle speed signal from this circuit. The wheel speed sensors produce an output that varies according to the vehicle speed. The wheel speed sensor output is received by the skid control ECU which uses this information to create the vehicle speed signal*a. The vehicle speed signal consists of pulses sent to the combination meter assembly from the skid control ECU. To create this signal, 12 V is output from IG2 which is behind a resistor in the combination meter assembly. This voltage is sent to the skid control ECU. The pulse signal is created by switching the transistor in the skid control ECU on and off, making the voltage on the wire drop to 0 V. A similar system is used for the output of this signal from the combination meter assembly via terminal +S. A voltage of 12 V or 5 V is applied to terminal +S from each ECU or relay that is connected to this terminal. The transistor in the combination meter assembly is controlled by the signal from the skid control ECU. When this transistor is turned on, this transistor makes the voltage supplied by the various ECUs (via their respective internal resistors) drop to 0 V. Each ECU connected to terminal +S of the combination meter assembly controls its respective system based on this pulse signal.

  • *a: This vehicle speed signal is created by the skid control ECU. There is no actual component that is referred to as the vehicle speed sensor. In addition, for some systems, vehicle speed information may be received via CAN communication.

HINT:

This circuit is used for the systems connected to terminal +S. This signal is not used for combination meter assembly operation. Combination meter assembly components such as the speedometer operate using data received via CAN communication.

WIRING DIAGRAM

for HV Model:
for Gasoline Model:

CAUTION / NOTICE / HINT

NOTICE:

  • w/ Smart Key System:

    Before replacing the certification ECU (smart key ECU assembly) refer to Registration.

    • for HV Model:

      Click here 2020 - 2021 MY RAV4 HV [10/2019 - 12/2021]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

    • for Gasoline Model:

      Click here 2020 MY RAV4 [10/2019 - 08/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

  • When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.
  • When replacing the radio and display receiver assembly, always replace it with a new one. If a radio and display receiver assembly which was installed to another vehicle is used, the following may occur:
    • A communication malfunction DTC may be stored.
    • The radio and display receiver assembly may not operate normally.

PROCEDURE

1.

CHECK ECU TERMINAL VOLTAGE (INPUT VOLTAGE)

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(a) Disconnect the combination meter assembly connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G18-36 (+S) - Body ground

Ignition switch ON

11 to 14 V

HINT:

If any of the ECUs specified in the wiring diagram supplies power to the combination meter assembly, the combination meter assembly will output a waveform.

Result

Proceed to

OK (for Gasoline Model)

A

OK (for HV Model)

B

NG

C

B

GO TO STEP 5

C

GO TO STEP 8

A

2.

CHECK COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE)

*a

Front view of wire harness connector

(to Brake Actuator Assembly [Skid Control ECU])

(a) Disconnect the brake actuator assembly (skid control ECU) connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

A39-34 (SP1) - Body ground

Ignition switch ON

11 to 14 V

NG

GO TO STEP 4

OK

3.

CHECK BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) (INPUT WAVEFORM)

*a

Component with harness connected

(Combination Meter Assembly)

*b

Waveform

(a) Check the input waveform.

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

Click here 2019 - 2022 MY RAV4 RAV4 HV [11/2018 - 10/2022]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

(2) Connect an oscilloscope to terminal G18-20 (SI) and body ground.

(3) Turn the ignition switch to ON.

(4) Turn a wheel slowly.

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

Item

Condition

Tester connection

G18-20 (SI) - Body ground

Tool setting

5 V/DIV., 20 ms./DIV.

Condition

Ignition switch ON, 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.

OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU)

4.

CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BRAKE ACTUATOR ASSEMBLY [SKID CONTROL ECU])

(a) Disconnect the G18 combination meter assembly connector.

(b) Disconnect the A39 brake actuator assembly (skid control ECU) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G18-20 (SI) - A39-34 (SP1)

Always

Below 1 Ω

G18-20 (SI) or A39-34 (SP1) - Body ground

Always

10 kΩ or higher

OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.

CHECK COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE)

*a

Front view of wire harness connector

(to Brake Booster with Master Cylinder Assembly [Skid Control ECU])

(a) Disconnect the brake booster with master cylinder assembly (skid control ECU) connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

A42-11 (SP1) - Body ground

Ignition switch ON

11 to 14 V

NG

GO TO STEP 7

OK

6.

CHECK BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU) (INPUT WAVEFORM)

*a

Component with harness connected

(Combination Meter Assembly)

*b

Waveform

(a) Check the input waveform.

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

Click here 2019 - 2022 MY RAV4 RAV4 HV [11/2018 - 10/2022]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

(2) Connect an oscilloscope to terminal G18-20 (SI) and body ground.

(3) Turn the ignition switch to ON.

(4) Turn a wheel slowly.

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

Item

Condition

Tester connection

G18-20 (SI) - Body ground

Tool setting

5 V/DIV., 20 ms./DIV.

Condition

Ignition switch ON, 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.

OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU)

7.

CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY [SKID CONTROL ECU])

(a) Disconnect the G18 combination meter assembly connector.

(b) Disconnect the A42 brake booster with master cylinder assembly (skid control ECU) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G18-20 (SI) - A42-11 (SP1)

Always

Below 1 Ω

G18-20 (SI) or A42-11 (SP1) - Body ground

Always

10 kΩ or higher

OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

8.

CHECK HARNESS AND CONNECTOR (EACH ECU - COMBINATION METER ASSEMBLY)

  • *1: for Gasoline Model
  • *2: w/ Audio and Visual System
  • *3: w/ Smart Key System
  • *4: w/ Navigation System
  • *5: for 9 Speakers
  • *6: w/o Occupant Classification System
  • *7: w/ Occupant Classification System

(a) Disconnect the combination meter assembly connector.

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(b) Disconnect the A24 ECM connector.*1

(c) Disconnect the G3 radio and display receiver assembly connector.*2

(d) Disconnect the G54 certification ECU (smart key ECU assembly) connector.*3

(e) Disconnect the H7*6 or G15*7 navigation ECU connector.*4

(f) Disconnect the M3 stereo component amplifier assembly connector.*5

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

G18-36 (+S) - Body ground

Always

10 kΩ or higher

Result

Proceed to

OK (for Gasoline Model)

A

OK (for HV Model)

B

NG

C

B

GO TO STEP 17

C

REPAIR OR REPLACE HARNESS OR CONNECTOR

A

9.

CHECK VEHICLE TYPE

(a) Check vehicle condition.

Result

Proceed to

w/ Smart Key System

A

w/o Smart Key System

B

B

GO TO STEP 11

A

10.

CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(a) Disconnect the combination meter assembly connector.

(b) Disconnect the G54 certification ECU (smart key ECU assembly) connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G18-36 (+S) - Body ground

Ignition switch ON

11 to 14 V

HINT:

If the result is as specified, there may be a short circuit in the certification ECU (smart key ECU assembly).

OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

NG

11.

CHECK VEHICLE TYPE

(a) Check vehicle condition.

Result

Proceed to

w/ Navigation System

A

w/o Navigation System

B

B

GO TO STEP 13

A

12.

CHECK NAVIGATION ECU

(a) Disconnect the combination meter assembly connector.

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(b) Disconnect the H7*1 or G15*2 navigation ECU connector.

  • *1: w/o Occupant Classification System
  • *2: w/ Occupant Classification System

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G18-36 (+S) - Body ground

Ignition switch ON

11 to 14 V

HINT:

If the result is as specified, there may be a short circuit in the navigation ECU.

OK

REPLACE NAVIGATION ECU

NG

13.

CHECK VEHICLE TYPE

(a) Check vehicle condition.

Result

Proceed to

w/ Audio and Visual System

A

w/o Audio and Visual System

B

B

GO TO STEP 15

A

14.

CHECK RADIO AND DISPLAY RECEIVER ASSEMBLY

(a) Disconnect the combination meter assembly connector.

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(b) Disconnect the G3 radio and display receiver assembly connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G18-36 (+S) - Body ground

Ignition switch ON

11 to 14 V

HINT:

If the result is as specified, there may be a short circuit in the radio and display receiver assembly.

OK

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

NG

15.

CHECK VEHICLE TYPE

(a) Check vehicle condition.

Result

Proceed to

for 9 Speakers

A

except 9 Speakers

B

B

REPLACE ECM

A

16.

CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY

(a) Disconnect the combination meter assembly connector.

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(b) Disconnect the M3 stereo component amplifier assembly connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G18-36 (+S) - Body ground

Ignition switch ON

11 to 14 V

HINT:

If the result is as specified, there may be a short circuit in the stereo component amplifier assembly.

OK

REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY

NG

REPLACE ECM

17.

CHECK VEHICLE TYPE

(a) Check vehicle condition.

Result

Proceed to

w/ Audio and Visual System

A

w/o Audio and Visual System

B

B

GO TO STEP 19

A

18.

CHECK RADIO AND DISPLAY RECEIVER ASSEMBLY

(a) Disconnect the combination meter assembly connector.

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(b) Disconnect the G3 radio and display receiver assembly connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G18-36 (+S) - Body ground

Ignition switch ON

11 to 14 V

HINT:

If the result is as specified, there may be a short circuit in the radio and display receiver assembly.

OK

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

NG

19.

CHECK VEHICLE TYPE

(a) Check vehicle condition.

Result

Proceed to

w/ Smart Key System

A

w/o Smart Key System

B

B

GO TO STEP 21

A

20.

CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(a) Disconnect the combination meter assembly connector.

(b) Disconnect the G54 certification ECU (smart key ECU assembly) connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G18-36 (+S) - Body ground

Ignition switch ON

11 to 14 V

HINT:

If the result is as specified, there may be a short circuit in the certification ECU (smart key ECU assembly).

OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

NG

21.

CHECK VEHICLE TYPE

(a) Check vehicle condition.

Result

Proceed to

w/ Navigation System

A

w/o Navigation System

B

B

REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY

A

22.

CHECK NAVIGATION ECU

(a) Disconnect the combination meter assembly connector.

*a

Front view of wire harness connector

(to Combination Meter Assembly)

(b) Disconnect the H7*1 or G15*2 navigation ECU connector.

  • *1: w/o Occupant Classification System
  • *2: w/ Occupant Classification System

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G18-36 (+S) - Body ground

Ignition switch ON

11 to 14 V

HINT:

If the result is as specified, there may be a short circuit in the navigation ECU.

OK

REPLACE NAVIGATION ECU

NG

REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY