SFI SYSTEM TERMINALS OF ECM

A005KA9E02

Tech Tips

The standard normal voltage between each pair of ECM terminals is shown in the table below. The appropriate conditions for checking each pair of terminals are also indicated. The result of checks should be compared with the standard normal voltage for that pair of terminals, displayed in the Specified Condition column. The illustration above can be used as a reference to identify the ECM terminal locations.

Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
A58-1 (BATT) - B23-16 (E1) Y - W-B Battery (for measuring battery voltage and for ECM memory) Always 11 to 14 V
A58-2 (+B) - B23-16 (E1) B - W-B Power source of ECM Ignition switch ON 11 to 14 V
A58-3 (+B2) - B23-16 (E1) B - W-B Power source of ECM Ignition switch ON 11 to 14 V
B23-29 (+BM) - B23-16 (E1) GR - W-B Power source of throttle actuator Always 11 to 14 V
B23-57 (IGT1) - B23-16 (E1) W - W-B

Ignition coil

(ignition signal)

 Idling

Pulse generation

(See waveform 1)
B23-56 (IGT2) - B23-16 (E1) V - W-B
B23-55 (IGT3) - B23-16 (E1) G - W-B
B23-54 (IGT4) - B23-16 (E1) LG - W-B
B23-102 (IGF1) - B23-16 (E1) Y - W-B

Ignition coil

(ignition confirmation signal)

 Ignition switch ON 4.5 to 5.5 V
Idling

Pulse generation

(See waveform 1)
B23-78 (NE+) - B23-110 (NE-) L - P Crankshaft position sensor Idling

Pulse generation

(See waveform 2)
B23-82 (VV1+) - B23-110 (NE-) W - P Camshaft position sensor Idling

Pulse generation

(See waveform 2)
B23-20 (#10) - B23-51 (E01) B - BR Fuel injector assembly Idling 11 to 14 V
B23-17 (#20) - B23-51 (E01) GR - BR
B23-18 (#30) - B23-51 (E01) P - BR
B23-19 (#40) - B23-51 (E01) L - BR
B23-23 (HA1A) - B23-52 (E04) G - W-B Air fuel ratio sensor heater (bank 1 sensor 1) Ignition switch ON 11 to 14 V
Idling

Pulse generation

(See waveform 3)
B23-133 (A1A+) - B23-16 (E1) R - W-B Air fuel ratio sensor (bank 1 sensor 1) Ignition switch ON Below 3.3 V*
B23-134 (A1A-) - B23-16 (E1) G - W-B Air fuel ratio sensor (bank 1 sensor 1) Ignition switch ON Below 3.0 V*
B23-22 (HT1B) - B23-51 (E01) L - BR Heated oxygen sensor heater (bank 1 sensor 2) Ignition switch ON 11 to 14 V
B23-103 (OX1B) - B23-135 (EX1B) B - GR Heated oxygen sensor (bank 1 sensor 2) Engine speed maintained at 2500 rpm for 2 minutes after warming up engine

Pulse generation

(See waveform 4)
B23-123 (KNK1) - B23-124 (EKNK) R - G Knock sensor Engine speed maintained at 4000 rpm after warming up engine

Pulse generation

(See waveform 5)
A58-44 (SPD) - B23-16 (E1) V - W-B Speed signal from combination meter Driving at 20 km/h (12 mph)

Pulse generation

(See waveform 6)
B23-93 (THW) - B23-94 (ETHW) V - BR Engine coolant temperature sensor Idling, Engine coolant temperature 80°C (176°F) 0.2 to 1.0 V
B23-90 (THA) - B23-122 (ETHA) P - G Intake air temperature sensor Idling, Intake air temperature 20°C (68°F) 1.5 to 3.0 V
B23-91 (VG) - B23-92 (E2G) GR - L Mass air flow meter Idling, Shift lever position neutral, air conditioner OFF 0.5 to 3.0 V
A58-27 (W) - B23-16 (E1) B - W-B MIL Ignition switch ON (MIL goes off) Below 1.5 V
Idling 11 to 14 V
B23-63 (NSW) - B23-16 (E1) BE - W-B Park/Neutral position switch signal Ignition switch ON Below 1.5 V
Cranking 5.5 V or more
A58-22 (STA) - B23-16 (E1) BR - W-B Starter signal Ignition switch ON Below 1.5 V
Cranking 5.5 V or more
B23-84 (VTA1) - B23-116 (ETA) Y - V Throttle position sensor Ignition switch ON, Accelerator pedal released 0.5 to 1.1 V
Ignition switch ON, Accelerator pedal fully depressed 3.2 to 4.8 V
B23-83 (VTA2) - B23-116 (ETA) GR - V Throttle position sensor Ignition switch ON, Accelerator pedal released 2.1 to 3.1 V
Ignition switch ON, Accelerator pedal fully depressed 4.6 to 5.0 V
B23-115 (VCTA) - B23-116 (ETA) W - V Power source of throttle position sensor Ignition switch ON 4.5 to 5.5 V
A58-53 (VCPA) - A58-52 (EPA) G - V Power source of accelerator pedal position sensor (for VPA) Ignition switch ON 4.5 to 5.5 V
A58-51 (VPA) - A58-52 (EPA) R - V Accelerator pedal position sensor Ignition switch ON, Accelerator pedal released 0.5 to 1.1 V
Ignition switch ON, Accelerator pedal fully depressed 2.6 to 4.5 V
A58-54 (VPA2) - A58-55 (EPA2) L - B Accelerator pedal position sensor Ignition switch ON, Accelerator pedal released 1.2 to 2.0 V
Ignition switch ON, Accelerator pedal fully depressed 3.4 to 5.0 V
A58-56 (VCP2) - A58-55 (EPA2) W - B Power source of accelerator pedal position sensor (for VPA2) Ignition switch ON 4.5 to 5.0 V
B23-60 (M+) - B23-59 (ME01) G - BR Throttle actuator Idling with warm engine

Pulse generation

(See waveform 7)
B23-30 (M-) - B23-59 (ME01) BR - BR Throttle actuator Idling with warm engine

Pulse generation

(See waveform 8)
A58-9 (STP) - B23-16 (E1) G - W-B Stop light switch Brake pedal depressed 7.5 to 14 V
Brake pedal released Below 1.5 V
A58-10 (ST1-) - B23-16 (E1) Y - W-B Stop light switch Ignition switch ON, Brake pedal depressed Below 1.5 V
Ignition switch ON, Brake pedal released 7.5 to 14 V
B23-76 (PRG) - B23-16 (E1) L - W-B Purge VSV Ignition switch ON 11 to 14 V
Idling, under purge control

Pulse generation

(See waveform 9)
A58-21 (FPC) - B23-16 (E1) LG - W-B Fuel pump control Ignition switch ON Below 1.2 V
A58-23 (TC) - B23-16 (E1) L - W-B Terminal TC of DLC3 Ignition switch ON 11 to 14 V
B23-75 (OC1+) - B23-74 (OC1-) BR - Y Camshaft timing oil control valve Idling

Pulse generation

(See waveform 10)
A58-13 (CANH) - B23-16 (E1) L - W-B CAN communication line Ignition switch ON

Pulse generation

(See waveform 11)
A58-26 (CANL) - B23-16 (E1) W - W-B CAN communication line Ignition switch ON

Pulse generation

(See waveform 12)
A58-37 (IGSW) - B23-16 (E1) R - W-B Ignition switch Ignition switch ON 11 to 14 V
A58-46 (MREL) - B23-16 (E1) GR - W-B EFI MAIN relay Ignition switch ON 11 to 14 V
B23-28 (EGR1) - B23-16 (E1) R - W-B EGR valve assembly Idling with warm engine

Pulse generation

(See waveform 13)
B23-27 (EGR2) - B23-16 (E1) LG - W-B EGR valve assembly Idling with warm engine

Pulse generation

(See waveform 14)
B23-26 (EGR3) - B23-16 (E1) W - W-B EGR valve assembly Idling with warm engine

Pulse generation)

(See waveform 13)
B23-25 (EGR4) - B23-16 (E1) Y - W-B EGR valve assembly Idling with warm engine

Pulse generation

(See waveform 14)
A58-31 (TACH) - B23-16 (E1) LG - W-B Engine speed Idling

Pulse generation

(See waveform 15)
A58-4 (ELS1) - B23-16 (E1) G - W-B Electric load Tail light switch on 7.5 to 14 V
Tail light switch off Below 1.5 V
A58-17 (ELS2) - B23-16 (E1) B - W-B Electric load Defogger switch on 7.5 to 14 V
Defogger switch off Below 1.5 V
B23-100 (ALT) - B23-16 (E1) G - W-B Generator assembly Ignition switch ON 11 to 14 V
A58-7 (FANL) - B23-16 (E1) R - W-B Fan No. 1 relay Ignition switch ON 11 to 14 V

Idling with A/C ON or

High engine coolant temperature

 Below 1.5 V
A58-8 (FANH) - B23-16 (E1) G - W-B Fan No. 2 relay Idling with high engine coolant temperature Below 1.5 V
B23-16 (E1) - Body ground W-B - Body ground Ground Always Below 1 Ω
B23-51 (E01) - Body ground BR - Body ground Ground Always Below 1 Ω
B23-21 (E02) - Body ground BR - Body ground Ground Always Below 1 Ω
B23-52 (E04) - Body ground W-B - Body ground Ground Always Below 1 Ω
A58-50 (EC) - Body ground W-B - Body ground Ground Always Below 1 Ω
B23-59 (ME01) - Body ground BR - Body ground Ground Always Below 1 Ω
B23-58 (GE01) - B23-16 (E1) BR - W-B Shielded earth (ground) circuit of throttle actuator Always Below 1 V

*: The ECM terminal voltage is constant regardless of the output voltage from the sensor.


  1. WAVEFORM 1

    A005GWGE01
    *a 5 V/DIV.

    Tech Tips

    The wavelength becomes shorter as the engine rpm increases.

  2. WAVEFORM 2

    A005LB3E01
    3. *a 5 V/DIV.
    *b 20 ms./DIV.

Tech Tips

The wavelength becomes shorter as the engine speed increases.

  • WAVEFORM 3

    A005KVNE01
    • *a 5 V/DIV.
    *b 10 ms./DIV.
    Air Fuel Ratio Sensor Heater Signal
    ECM Terminal Name Between HA1A and E04
    Tester Range 5 V/DIV., 10 ms./DIV.
    Condition Idling

    Tech Tips

    The duty ratio varies depending on the engine driving condition.

  • WAVEFORM 4

    A005LRKE05
    *1 0.2 V/DIV.
    *2 200 ms./DIV.
    Heated Oxygen Sensor Signal
    ECM Terminal Name Between OX1B and EX1B
    Tester Range 0.2 V/DIV., 200 ms./DIV.
    Condition Engine speed maintained at 2500 rpm for 2 minutes after warming up engine

    Tech Tips

    In the Data List, the item O2S B1 S2 shows the values input to the ECM from the heated oxygen sensor.

  • WAVEFORM 5

    A005LLDE03
    *a 1 V/DIV.
    *b 1 ms./DIV.

    Tech Tips


    • The wavelength becomes shorter as the engine rpm increases.

    • The waveforms and amplitudes displayed differ slightly depending on the vehicle.

  • WAVEFORM 6

    A005JXAE01
    • *a 5 V/DIV.
    *b 20 ms./DIV.

    Tech Tips

    The wavelength becomes shorter as the vehicle speed increases.

  • WAVEFORM 7

    A005GSPE03
    • *a 5 V/DIV.
    *b 1 ms./DIV.
    Throttle Actuator Positive Terminal Signal
    ECM Terminal Name Between M+ and ME01
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The duty ratio varies depending on the throttle actuator operation.

  • WAVEFORM 8

    A005JL7E01
    *a 5 V/DIV.
    *b 1 ms./DIV.
    Throttle Actuator Negative Terminal Signal
    ECM Terminal Name Between M- and ME01
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The duty ratio varies depending on the throttle actuator operation.

  • WAVEFORM 9

    A005K60E01
    *1 10 V/DIV.
    *2 20 ms./DIV.

    Tech Tips

    If the waveform is not similar to the illustration, check the waveform again after idling for 10 minutes or more.

  • WAVEFORM 10

    A005LNSE03
    • *a 5 V/DIV.
    *b 1 ms./DIV.
    Camshaft Timing Oil Control Valve Assembly Signal
    ECM Terminal Name Between OC1+ and OC1-
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling

  • WAVEFORM 11

    A005LG6E01
    *a 1 V/DIV.
    *b 10 μs./DIV.
    CAN Communication Signal (Reference)
    ECM Terminal Name Between CANH and E1
    Tester Range 1 V/DIV., 10 μsec./DIV.
    Condition Ignition switch ON

    Tech Tips

    The waveform varies depending on the CAN communication signal.

  • WAVEFORM 12

    A005JX1E01
    *a 1 V/DIV.
    *b 10 μs./DIV.
    CAN Communication Signal (Reference)
    ECM Terminal Name Between CANL and E1
    Tester Range 1 V/DIV., 10 μsec./DIV.
    Condition Ignition switch ON

    Tech Tips

    The waveform varies depending on the CAN communication signal.

  • WAVEFORM 13

    A005K54E04
    *1 10 V/DIV.
    *2 20 ms./DIV.
    EGR Valve Signal
    ECM Terminal Name

    CH1: Between EGR 1 and E1

    CH2: Between EGR 3 and E1
    Tester Range 10 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

  • WAVEFORM 14

    A005GFEE04
    *1 10 V/DIV.
    *2 20 ms./DIV.
    EGR Valve Signal
    ECM Terminal Name

    CH1: Between EGR 2 and E1

    CH2: Between EGR 4 and E1
    Tester Range 10 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

  • WAVEFORM 15

    A005HPQE01
    *a 5 V/DIV.
    *b 10 ms./DIV.
    Engine Speed Signal
    ECM Terminal Name Between TACH and E1
    Tester Range 5 V/DIV., 10 ms./DIV.
    Condition Idling

    Tech Tips

    The wavelength becomes shorter as the engine rpm increases.