Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001N5OG
Model Year Start: 2021 Model: GR Corolla Prod Date Range: [04/2020 - 06/2021]
Title: METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM (for Gasoline Model): TERMINALS OF ECU; 2021 MY Corolla Corolla Hatchback GR Corolla [04/2020 - 06/2021]

TERMINALS OF ECU

COMBINATION METER ASSEMBLY

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

  • Terminal No. (Symbol)

    Wiring Color

    Terminal Description

    Signal Input/output

    Condition

    Specified Condition

    I4-1 (B) - Body ground
    • LA-SB - Body ground*4
    • SB - Body ground*5

    Battery

    -

    Always

    11 to 14 V

    I4-9 (CANH)

    L

    CAN communication line

    Input/output

    -

    -

    I4-10 (MSCL)*1, *2
    • Y*4
    • W*5

    Local bus communication line

    Input/output

    -

    -

    I4-11 (SW3) - Body ground

    BR - Body ground

    Light control rheostat (Ground)

    -

    Always

    Below 1 Ω

    I4-14 (FV) - Body ground

    GR - Body ground

    Fuel sender gauge (Power source)

    Input

    Ignition switch ON

    Pulse generation

    (See waveform 2)

    I4-15 (MSTI) - Body ground

    V - Body ground

    Steering pad switch signal

    Input

    Ignition switch ON, up, down, right and left switches on steering pad switch not pushed

    4.8 to 5.2 V

    I4-16 (SW2) - Body ground

    P - Body ground

    Light control rheostat signal

    Input

    Ignition switch ON, light control rheostat knob fully turned downward → fully turned upward

    Below 1 V → 4 to 6 V

    (Gradually change)

    I4-17 (TC) - Body ground

    V - Body ground

    Tail cancel switch signal

    Input

    Ignition switch ON, light control rheostat knob not fully turned upward (Tail cancel switch off) → fully turned upward (Tail cancel switch on)

    Below 1 V → 4 to 6 V

    I4-19 (EP) - Body ground

    W-B - Body ground

    Ground

    -

    Always

    Below 1 Ω

    I4-20 (SI) - Body ground
    • GR - Body ground*6
    • BR - Body ground*7

    Speed signal for other system (Input)

    Input

    Ignition switch ON, wheel being rotated

    Pulse generation

    (See waveform 1)

    I4-22 (B) - Body ground

    G - Body ground

    Battery

    -

    Always

    11 to 14 V

    I4-23 (ES) - Body ground

    W-B - Body ground

    Ground

    -

    Always

    Below 1 Ω

    I4-24 (FE&B) -Body ground

    P - Body ground

    Fuel sender gauge (Ground)

    -

    Always

    Below 1 Ω

    I4-25 (CANL)

    W

    CAN communication line

    Input/output

    -

    -

    I4-27 (MSCH)*1, *2

    LG

    Local bus communication line

    Input/output

    -

    -

    I4-31 (FR) - I4-24 (FE&B)

    R - P

    Fuel level signal

    Input

    Ignition switch ON, fuel level full → low (fuel level warning light on)

    Pulse generation

    (See waveform 3)

    I4-32 (MSM+) - Body ground

    GR - Body ground

    Steering pad switch signal

    Input

    Ignition switch ON, OK and back switches on steering pad switch not pushed

    4.8 to 5.2 V

    I4-34 (SW1) - Body ground

    R - Body ground

    Light control rheostat (Power source)

    Input

    Ignition switch ON

    4 to 6 V

    I4-35 (ILL-) - Body ground
    • W-B - Body ground*4
    • L - Body ground*5

    Illumination signal

    Output

    Taillights off → on

    Below 1 V → Pulse generation

    I4-36 (+S) - Body ground
    • L - Body ground*4
    • SB - Body ground*5

    Speed signal for other systems (Output)

    Output

    Ignition switch ON, wheel being rotated

    Pulse generation

    (See waveform 1)

    I4-38 (IG+) - Body ground

    LG - Body ground

    Ignition switch signal

    Input

    Ignition switch off → Ignition switch ON

    Below 1 V → 11 to 14 V

    I5-1 (LL) - Body ground
    • LA-V - Body ground*4
    • R - Body ground*5

    LH turn switch signal

    Output

    LH turn indicator light off → blinking

    Below 1 V → 11 to 14 V ←→ Below 1 V

    I5-2 (LR) - Body ground
    • LA-V - Body ground*4
    • V - Body ground*5

    RH turn switch signal

    Output

    RH turn indicator light off → blinking

    Below 1 V → 11 to 14 V ←→ Below 1 V

    I5-5 (TRNL) - Body ground

    V - Body ground

    LH turn switch signal

    Output

    LH turn indicator light off → blinking

    Below 1 V → 11 to 14 V ←→ Below 1 V

    I5-6 (TRNR) - Body ground

    G - Body ground

    RH turn switch signal

    Output

    RH turn indicator light off → blinking

    Below 1 V → 11 to 14 V ←→ Below 1 V

    I5-7 (LP) - Body ground
    • R - Body ground*4
    • P - Body ground*5

    Security indicator signal

    Input

    Security indicator light off → blinking

    Below 2 V → Pulse generation

    I5-14 (WLVL) - Body ground*3

    L - Body ground

    Washer fluid level signal

    Input

    Ignition switch ON, washer fluid level not low → low

    11 to 14 V → Below 1 V

    I5-16 (SW) - Body ground

    P - Body ground

    Brake fluid level signal

    Input

    Ignition switch ON, brake fluid level not low (brake warning light off) → low (brake warning light on)

    11 to 14 V → Below 1 V

    I5-17 (HAZ) - Body ground

    P - Body ground

    Hazard warning signal switch signal

    Input

    Hazard warning signal switch off → pushed

    11 to 14 V → Below 1 V

    I5-19 (RCSB) - Body ground

    W - Body ground

    Rear center seat belt warning signal

    Input

    Ignition switch ON, rear center seat belt unfastened → fastened

    Below 1 V → 11 to 14 V

    I5-23 (S) - Body ground*9

    G - Body ground

    Engine oil pressure signal

    Input

    Engine started → not started

    11 to 14 V → Below 1 V

    I5-24 (INT) - Body ground*10

    B - Body ground

    Tire pressure warning system signal

    Output

    Ignition switch ON, OK switch on steering pad switch not pushed

    8 to 15 V

    I5-31 (OILW) - Body ground*8

    B - Body ground

    Engine oil level signal

    Input

    Ignition switch ON, engine oil level not low → low

    Below 1 V → 11 to 14 V

    I5-32 (VCM) - Body ground

    L - Body ground

    Vacuum warning switch signal

    Input

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

    11 to 14 V → Below 1 V

    I5-35 (RRSB) - Body ground

    R - Body ground

    Rear right seat belt warning signal

    Input

    Ignition switch ON, rear right seat belt unfastened → fastened

    Below 1 V → 11 to 14 V

    I5-36 (RLSB) - Body ground

    G - Body ground

    Rear left seat belt warning signal

    Input

    Ignition switch ON, rear left seat belt unfastened → fastened

    Below 1 V → 11 to 14 V
    • *1: w/ Audio Tab Display
    • *2: w/ Headup Display System
    • *3: w/ Washer Fluid Level Warning
    • *4: for Hatchback
    • *5: for Sedan
    • *6: w/ Smart Key System
    • *7: w/o Smart Key System
    • *8: for M20A-FKS
    • *9: for 2ZR-FAE
    • *10: w/ Tire Pressure Warning System

(b) Check for pulses according to the value(s) in the table below.

  • Waveform 1:

    Item

    Condition

    Tester connection
    • I4-20 (SI) - Body ground
    • I4-36 (+S) - Body ground

    Tool setting

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

    Condition

    Ignition switch ON, 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

    I4-14 (FV) - Body ground

    Tool setting

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

    Condition

    Ignition switch ON

    Specified Condition

    4.5 to 5.5 V

  • Waveform 3:

    Item

    Condition

    Tester connection

    I4-31 (FR) - I4-24 (FE&B)

    Tool setting

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

    Condition

    Ignition switch ON, fuel level full → low (fuel level warning light on)

    HINT:

    (A) will depending on the fuel level.

    • Fuel level full: 4.0 to 4.6 V
    • Fuel level low (fuel level warning light on): 0.3 to 1.1 V