Toyota Avalon (XX50): System Diagram. Tachometer Malfunction. Terminals Of Ecu

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Vehicle Interior / Meter / Gauge / Display / Meter / Gauge System(for Gasoline Model) / System Diagram. Tachometer Malfunction. Terminals Of Ecu

System Diagram

SYSTEM DIAGRAM

HINT:

Refer to System Diagram of CAN Communication System.

Click here

COMBINATION METER ASSEMBLY DIAGRAM

TURN SIGNAL LIGHT DIAGRAM

(a) LH Side

(b) RH Side

ILLUMINATION DIAGRAM

SPEED SIGNAL DIAGRAM

Tachometer Malfunction

DESCRIPTION

In this circuit, the combination meter assembly receives engine speed signals from the ECM via CAN communication. The combination meter assembly displays the engine speed calculated based on the data received from the ECM.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • 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.
  • Before replacing the ECM, refer to Registration.

    Click here

PROCEDURE

1.

CHECK CAN COMMUNICATION SYSTEM

(a) Check if CAN communication DTCs are output.

Click here

Result

Proceed to

CAN communication DTCs are not output

A

CAN communication DTCs are output

B
B

GO TO CAN COMMUNICATION SYSTEM

A

2.

CHECK FOR DTC (SFI SYSTEM)

(a) Check if SFI system DTCs are output.

Powertrain > Engine > Trouble Codes

Result

Proceed to

DTCs are not output

A

DTCs are output

B
B

GO TO SFI SYSTEM

A

3.

PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Combination Meter / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > Combination Meter > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

TachoMeter Operation (0rpm)

Tachometer (0 rpm)

ON

-

TachoMeter Operation (1000rpm)

Tachometer (1000 rpm)

ON

-

TachoMeter Operation (2000rpm)

Tachometer (2000 rpm)

ON

-

TachoMeter Operation (3000rpm)

Tachometer (3000 rpm)

ON

-

TachoMeter Operation (4000rpm)

Tachometer (4000 rpm)

ON

-

TachoMeter Operation (5000rpm)

Tachometer (5000 rpm)

ON

-

TachoMeter Operation (6000rpm)

Tachometer (6000 rpm)

ON

-

TachoMeter Operation (7000rpm)

Tachometer (7000 rpm)

ON

-
Body Electrical > Combination Meter > Active Test

Tester Display

TachoMeter Operation (0rpm)
Body Electrical > Combination Meter > Active Test

Tester Display

TachoMeter Operation (1000rpm)
Body Electrical > Combination Meter > Active Test

Tester Display

TachoMeter Operation (2000rpm)
Body Electrical > Combination Meter > Active Test

Tester Display

TachoMeter Operation (3000rpm)
Body Electrical > Combination Meter > Active Test

Tester Display

TachoMeter Operation (4000rpm)
Body Electrical > Combination Meter > Active Test

Tester Display

TachoMeter Operation (5000rpm)
Body Electrical > Combination Meter > Active Test

Tester Display

TachoMeter Operation (6000rpm)
Body Electrical > Combination Meter > Active Test

Tester Display

TachoMeter Operation (7000rpm)

OK:

Tachometer indication is normal.

OK

REPLACE ECM

NG

REPLACE COMBINATION METER ASSEMBLY

Terminals Of Ecu

TERMINALS OF ECU

COMBINATION METER ASSEMBLY

(a) Measure the voltage and resistance and check for pulses according to the value(s) in the table below.

Terminal No. (Symbol)

Wiring Color

Terminal Description

Signal Input/Output

Condition

Specified Condition

G16-1 (ILL-) - Body ground

LA-L - Body ground

Illumination signal

Output

Taillights off → Taillights on

Below 1 V → Pulse generation

G16-2 (EP) - Body ground

W-B - Body ground

Ground

-

Always

Below 1 Ω

G16-4 (INT) - Body ground

L - Body ground

Tire pressure warning ECU and receiver signal

Output
  • Engine switch on (IG)
  • Steering pad switch assembly operated, "TPWS" selected on the multi-information display and "OK" switch (steering pad switch assembly) pressed and held → "OK" switch (steering pad switch assembly) off

Below 1.5 V → 8 to 15 V

G16-5 (SI) - Body ground

W - Body ground

Speed signal for other systems (Input)

Input

Engine switch on (IG), wheel being rotated

Pulse generation (See waveform 1)

G16-6 (+S) - Body ground

L - Body ground

Speed signal for other systems (Output)

Output

Engine switch on (IG), wheel being rotated

Pulse generation (See waveform 1)

G16-7 (VCM) - Body ground

BE - Body ground

Vacuum warning switch signal

Input

Engine started, vacuum warning switch off (brake warning light off) → Vacuum warning switch on (brake warning light on)

11 to 14 V → Below 1 V

G16-9 (S) - Body ground

LA-R - Body ground

Engine oil pressure signal

Input

Engine not started → Engine started

Below 1 V → 11 to 14 V

G16-12 (SW) - Body ground

G - Body ground

Brake fluid level signal

Input

Engine switch on (IG), brake fluid level not low (brake warning light off) → Brake fluid level low (brake warning light on)

11 to 14 V → Below 1 V

G16-14 (FR) - G16-33 (FE)

LG - BE

Fuel level signal

Input

Engine switch on (IG), fuel level full → Fuel level low (fuel level warning light on)

Pulse generation (See waveform 2)

G16-15 (FV) - Body ground

GR - Body ground

Fuel sender gauge (Power source)

-

Engine switch on (IG)

Pulse generation (See waveform 3)

G16-17 (WLVL) - Body ground

LG - Body ground

Washer fluid level signal

Input

Engine switch on (IG), washer fluid level not low → Washer fluid level low

11 to 14 V → Below 1 V

G16-18 (RLMT) -Body ground

BE - Body ground

Rear seat belt warning light LH signal

Output

Engine switch on (IG), rear seat belt warning light LH (radio and display receiver assembly) off → Rear seat belt warning light LH (radio and display receiver assembly) on

11 to 14 V → Below 1 V

G16-19 (RCMT) -Body ground

R - Body ground

Rear seat belt warning light center signal

Output

Engine switch on (IG), rear seat belt warning light center (radio and display receiver assembly) off → Rear seat belt warning light center (radio and display receiver assembly) on

11 to 14 V → Below 1 V

G16-20 (RRMT) -Body ground

G - Body ground

Rear seat belt warning light RH signal

Output

Engine switch on (IG), rear seat belt warning light RH (radio and display receiver assembly) off → Rear seat belt warning light RH (radio and display receiver assembly) on

11 to 14 V → Below 1 V

G16-21 (ES) - Body ground

W-B - Body ground

Ground

-

Always

Below 1 Ω

G16-24 (RLSB) - Body ground

SB - Body ground

Rear seat belt buckle switch LH signal

Input

Engine switch on (IG), rear seat belt LH unfastened → Fastened

Below 1 V → 11 to 14 V

G16-25 (RCSB) - Body ground

B - Body ground

Rear seat belt buckle switch center signal

Input

Engine switch on (IG), rear seat belt center unfastened → Fastened

Below 1 V → 11 to 14 V

G16-26 (RRSB) - Body ground

LG - Body ground

Rear seat belt buckle switch RH signal

Input

Engine switch on (IG), rear seat belt RH unfastened → Fastened

Below 1 V → 11 to 14 V

G16-27 (OILW) - Body ground

W - Body ground

Engine oil level signal

Input

Engine switch on (IG), engine oil level not low → Engine oil level low

Below 1 V → 11 to 14 V

G16-28 (MSM+) - Body ground

GR - Body ground

Steering pad switch assembly signal

Input

Engine switch on (IG), up, down, right and left switches on steering pad switch assembly not pushed

4.8 to 5.2 V

G16-29 (MSTI) - Body ground

R - Body ground

Steering pad switch assembly signal

Input

Engine switch on (IG), OK and back switches on steering pad switch assembly not pushed

4.8 to 5.2 V

G16-31 (CANL)

W

CAN communication line

Input/Output

-

-

G16-32 (CANH)

B

CAN communication line

Input/Output

-

-

G16-36 (TX+)

G

Local bus communication line

Input/Output

-

-

G16-37 (TX-)

W

Local bus communication line

Input/Output

-

-

G16-39 (IG+) - Body ground

GR - Body ground

Engine switch signal

-

Engine switch off → Engine switch on (IG)

Below 1 V → 11 to 14 V

G16-40 (B) - Body ground

LA-B - Body ground

Battery

-

Always

11 to 14 V

G15-1 (ODO) - Body ground

LA-L - Body ground

ODO/TRIP switch signal

Input

Engine switch on (IG), ODO/TRIP switch (trip switch) not pushed

4.8 to 5.2 V

G15-2 (TR) - Body ground

L - Body ground

Light control rheostat switch signal

Input

Engine switch on (IG), light control rheostat up switch (trip switch) and light control rheostat down switch (trip switch) not pushed

4.8 to 5.2 V

G15-3 (HAZ) - Body ground

LA-R - Body ground

Hazard warning switch signal

Input

Hazard warning switch assembly (radio and display receiver assembly) off → Hazard warning switch assembly (radio and display receiver assembly) pushed

11 to 14 V → Below 1 V

G15-5 (SW3) - Body ground

LA-B - Body ground

Ground for trip switch

-

Always

Below 1 Ω

G15-7 (LR) - Body ground

LA-G - Body ground

Front turn signal light RH signal

Output

Engine switch on (IG), RH turn indicator light off → RH turn indicator light blinking

Below 1 V → 11 to 14 V ←→ Below 1 V

G15-8 (B) - Body ground

LA-B - Body ground

Battery

-

Always

11 to 14 V

G15-10 (TRNL) - Body ground

BE - Body ground

Rear turn signal light LH signal

Output

Engine switch on (IG), LH turn indicator light off → LH turn indicator light blinking

Below 1 V → 11 to 14 V ←→ Below 1 V

G15-11 (LL) - Body ground

LA-LG - Body ground

Front turn signal light LH signal

Output

Engine switch on (IG), LH turn indicator light off → LH turn indicator light blinking

Below 1 V → 11 to 14 V ←→ Below 1 V

G15-13 (TRNR) - Body ground

BE - Body ground

Rear turn signal light RH signal

Output

Engine switch on (IG), RH turn indicator light off → RH turn indicator light blinking

Below 1 V → 11 to 14 V ←→ Below 1 V
  • Waveform 1:

    Item

    Condition

    Tester connection
    • G16-5 (SI) - Body ground
    • G16-6 (+S) - Body ground

    Tool setting

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

    Condition

    Engine switch on (IG), wheel being rotated

    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.

  • Waveform 2:

    Item

    Condition

    Tester connection

    G16-14 (FR) - G16-33 (FE)

    Tool setting

    2.5 V/DIV., 20 ms./DIV.

    Condition

    Engine switch on (IG), fuel level full → Fuel level low (fuel level warning light on)

    HINT:

    • (A) will depending on the fuel level.
    • Engine switch on (IG), fuel level full → Fuel level low (fuel level warning light on) (4.2 to 4.6 V → 0.3 to 1.7 V)
  • Waveform 3:

    Item

    Condition

    Tester connection

    G16-15 (FV) - Body ground

    Tool setting

    2.5 V/DIV., 20 ms./DIV.

    Condition

    Engine switch on (IG)

    HINT:

    Engine switch on (IG) (4.5 to 5.5 V)

Speedometer Malfunction. Steering Pad Switch Circuit. System Description

Lost Communication With ECM/PCM "A" Missing Message (U010087,...,U113387)

See More:

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual > Electronically Controlled Brake System(for Gasoline Model): VSC OFF Switch Circuit
DESCRIPTION The skid control ECU (brake actuator assembly) is connected to the combination meter assembly via CAN communication. Pressing the VSC OFF switch turns off TRAC operation, and pressing and holding this switch turns off TRAC and VSC operation. If TRAC and VSC operations are turned off, "Tr ...

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual

© 2025 Copyright vehicle-interior.tavalon.net
0.1381