SFI SYSTEM TERMINALS OF ECM

A01FIC4E94

Tech Tips

The standard normal voltage between each pair of the ECM terminals is shown in the table below. The appropriate conditions for checking each pair of the 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
A19-7 (BATT) - F4-1 (E1) L - BR Battery (for measuring battery voltage and for ECM memory) Always 11 to 14 V
F1-1 (+BM) - F4-1 (E1) P - BR Power source of throttle motor Always 11 to 14 V
A19-8 (IGSW) - F4-1 (E1) B - BR Engine switch Engine switch on (IG) 11 to 14 V
A21-2 (+B) - F4-1 (E1) P - BR Power source of ECM Engine switch on (IG) 11 to 14 V
F1-12 (OC1+) - F1-11 (OC1-) W - Y Camshaft timing oil control valve (Intake camshaft (bank 1)) Idling

Pulse generation

(see waveform 1)
F1-10 (OC2+) - F1-9 (OC2-) LG - L Camshaft timing oil control valve (Intake camshaft (bank 2)) Idling

Pulse generation

(see waveform 1)
F2-4 (OE1+) - F2-3 (OE1-) LG - B Camshaft timing oil control valve (Exhaust camshaft (bank 1)) Idling

Pulse generation

(see waveform 1)
F3-18 (OE2+) - F3-28 (OE2-) W - G Camshaft timing oil control valve (Exhaust camshaft (bank 2)) Idling

Pulse generation

(see waveform 1)
A19-3 (MREL) - F4-1 (E1) Y - BR EFI MAIN relay Engine switch on (IG) 11 to 14 V
A19-4 (IREL) - F4-1 (E1) GR - BR INJ relay Engine switch on (IG) 11 to 14 V
F1-18 (VC) - F1-28 (E2) L - BR Power source for sensors (specific voltage) Engine switch on (IG) 4.5 to 5.5 V
F1-25 (VG) - F1-24 (E2G) R - W Mass air flow meter Idling, Shift lever position neutral, A/C switch off 0.5 to 3.0 V
F1-22 (THA) - F1-28 (E2) G - BR Intake air temperature sensor Idling, Intake air temperature 0 to 80°C (32 to 176°F) 0.5 to 3.4 V
F1-19 (THW) - F1-28 (E2) R - BR Engine coolant temperature sensor Idling, Engine coolant temperature 60 to 80°C (140 to 176°F) 0.2 to 1.0 V
F2-26 (VTA) - F1-28 (E2) W - BR Throttle position sensor (for engine control) Accelerator pedal fully released 0.5 to 1.1 V
Accelerator pedal fully depressed 3.2 to 4.8 V
F2-27 (VTA2) - F1-28 (E2) L - BR Throttle position sensor (for sensor malfunction detection) Accelerator pedal fully released 2.1 to 3.1 V
Accelerator pedal fully depressed 4.6 to 5.0 V
A19-29 (VPA) - A19-20 (EPA) V - Y Accelerator pedal position sensor (for engine control) Engine switch on (IG), Accelerator pedal fully released 0.5 to 1.1 V
Engine switch on (IG), Accelerator pedal fully depressed 2.6 to 4.5 V
A19-28 (VPA2) - A19-21 (EPA2)

G - BR*2

G - G*3

 Accelerator pedal position sensor (for sensor malfunctioning detection) Engine switch on (IG), Accelerator pedal fully released 1.2 to 2.0 V
Engine switch on (IG), Accelerator pedal fully depressed 3.4 to 5.0 V
A19-23 (VCPA) - A19-21 (EPA2)

L - BR*2

L - G*3

 Power source of accelerator pedal position sensor (for VPA) Engine switch on (IG) 4.5 to 5.5 V
A19-22 (VCP2) - A19-21 (EPA2)

LG*2 - BR*2

R*3 - G*3

 Power source of accelerator pedal position sensor (for VPA2) Engine switch on (IG) 4.5 to 5.5 V

F4-5 (HA1A) - F4-4 (E04)

F4-6 (HA2A) - F3-1 (E05)

L - W-B

B - W-B

 Air fuel ratio sensor heater Idling

Pulse generation

(see waveform 2)
Engine switch on (IG) 11 to 14 V
F3-23 (A1A+) - F4-1 (E1) R - BR Air fuel ratio sensor Engine switch on (IG) 3.3 V*1
F3-21 (A2A+) - F4-1 (E1) B - BR Air fuel ratio sensor Engine switch on (IG) 3.3 V*1
F3-22 (A1A-) - F4-1 (E1) G - BR Air fuel ratio sensor Engine switch on (IG) 2.9 V*1
F3-20 (A2A-) - F4-1 (E1) W - BR Air fuel ratio sensor Engine switch on (IG) 2.9 V*1
A21-4 (HT1B) - A21-5 (E03) L - BR Heated oxygen sensor heater Idling Below 3.0 V
A21-3 (HT2B) - A21-5 (E03) LG - BR Heated oxygen sensor heater Idling Below 3.0 V
A21-4 (HT1B) - A21-5 (E03) L - BR Heated oxygen sensor heater Engine switch on (IG) 11 to 14 V
A21-3 (HT2B) - A21-5 (E03) LG - BR Heated oxygen sensor heater Engine switch on (IG) 11 to 14 V

A21-26 (OX1B) - F1-28 (E2)

A21-27 (OX2B) - F1-28 (E2)

R - BR

B - BR

 Heated oxygen sensor Engine speed maintained at 2500 rpm for 2 minutes after warming up engine

Pulse generation

(see waveform 3)
F4-26 (KNK1) - F4-33 (EKNK) B - W Knock sensor Engine speed maintained at 4000 rpm after warming up engine

Pulse generation

(see waveform 4)
F4-25 (KNK2) - F4-32 (EKN2) R - G Knock sensor Engine speed maintained at 4000 rpm after warming up engine

Pulse generation

(see waveform 4)
F2-24 (VV1+) - F2-32 (VV1-) Y - V Variable valve timing (VVT) sensor (Intake camshaft (bank 1)) Idling

Pulse generation

(see waveform 5)
F3-19 (VV2+) - F3-29 (VV2-) GR - W Variable valve timing (VVT) sensor (Intake camshaft (bank 2)) Idling

Pulse generation

(see waveform 5)
F1-27 (NE+) - F1-34 (NE-) W - B Crankshaft position sensor Idling

Pulse generation

(see waveform 5, 6)
F1-26 (EV1+) - F1-33 (EV1-) P - LG Variable valve timing (VVT) sensor (Exhaust camshaft (bank 1)) Idling

Pulse generation

(see waveform 6)
F4-22 (EV2+) - F4-29 (EV2-) G - R Variable valve timing (VVT) sensor (Exhaust camshaft (bank 2)) Idling

Pulse generation

(see waveform 6)

F3-27 (IGT1) - F4-1 (E1)

F2-23 (IGT2) - F4-1 (E1)

F3-26 (IGT3) - F4-1 (E1)

F2-22 (IGT4) - F4-1 (E1)

F3-25 (IGT5) - F4-1 (E1)

F2-21 (IGT6) - F4-1 (E1)

LG - BR

L - BR

V - BR

P - BR

V - BR

W- BR

 Ignition coil (ignition signal) Idling

Pulse generation

(see waveform 7)

F3-32 (IGF1) - F4-1 (E1)

F2-28 (IGF2) - F4-1 (E1)

G - BR

V - BR

 Ignition coil (ignition confirmation signal) Engine switch on (IG) 4.5 to 5.0 V
Idling

Pulse generation

(see waveform 7)
F1-17 (PRG) - F4-1 (E1) W - BR Purge VSV Engine switch on (IG) 11 to 14 V
Idling

Pulse generation

(see waveform 8)
A19-24 (SPD) - F4-1 (E1) SB - BR Speed signal from combination meter Driving at 20 km/h (12 mph)

Pulse generation

(see waveform 9)
A21-20 (STA) - F4-1 (E1) R - BR Starter signal Cranking 5.5 V or higher
A19-13 (STP) - F4-1 (E1) R - BR Stop light switch Brake pedal depressed 7.5 to 14 V
A19-13 (STP) - F4-1 (E1) R - BR Stop light switch Brake pedal released Below 1.5 V
A19-12 (ST1-) - F4-1 (E1) GR - BR Stop light switch Engine switch on (IG), Brake pedal depressed Below 1.5 V
Engine switch on (IG), Brake pedal released 7.5 to 14 V
F2-7 (M+) - F2-5 (ME01) B - W-B Throttle actuator Idling with warm engine

Pulse generation

(see waveform 10)
F2-6 (M-) - F2-5 (ME01) W - W-B Throttle actuator Idling with warm engine

Pulse generation

(see waveform 11)
A19-11 (W) - F4-1 (E1) B - BR MIL

Engine switch on (IG)

(MIL goes on)

 Below 3.0 V
Idling 0 to 3.0 V
A21-21 (TC) - F4-1 (E1) LG - BR Terminal TC of DLC3 Engine switch on (IG) 11 to 14 V
A19-15 (TACH) - F4-1 (E1) GR - BR Engine speed Idling

Pulse generation

(see waveform 12)
A21-35 (ACIS) - F4-1 (E1) Y - BR Intake air control valve actuator for ACIS Engine switch on (IG) 11 to 14 V
Engine speed is 2200 to 4300 rpm and throttle opening angle is 30° or more 0 to 3.0 V
F1-16 (VPMP) - F4-1 (E1) G - BR Vent valve (built into canister pump module) Engine switch on (IG) 11 to 14 V
F1-15 (MPMP) - F4-1 (E1) R - BR Vacuum pump (built into canister pump module) Leak detection pump off 0 to 3.0 V
Leak detection pump on 9 to 14 V
F1-31 (PPMP) - F1-28 (E2) W - BR Pressure sensor (built into canister pump module) Engine switch on (IG) 3.0 to 3.6 V

F4-20 (#1) - F4-1 (E1)

F4-10 (#2) - F4-1 (E1)

F4-9 (#3) - F4-1 (E1)

F4-19 (#4) - F4-1 (E1)

F4-8 (#5) - F4-1 (E1)

F4-18 (#6) - F4-1 (E1)

LG - BR

L - BR

R - BR

P - BR

V - BR

W - BR

 Fuel injector Engine switch on (IG) 0 to 5 V
Idling Pulse generation (see waveform 13)
F2-13 (INJ1) - F4-1 (E1) GR - BR Injector injection confirmation signal Idling Pulse generation (see waveform 13)
F2-12 (INJ2) - F4-1 (E1) B - BR Injector injection confirmation signal Idling Pulse generation (see waveform 13)
F2-15 (INJ3) - F4-1 (E1) Y - BR Injector injection confirmation signal Idling Pulse generation (see waveform 13)
F3-10 (FPF1) - F4-1 (E1) G - BR Fuel pump for high pressure Idling

Pulse generation

(see waveform 14)
F3-11 (FPD) - F4-1 (E1) LG - BR Fuel pump for high pressure Idling

Pulse generation

(see waveform 14)
F4-27 (PR) - F1-28 (E2) V - BR Fuel pressure sensor Idling with warm engine 1.2 to 3.3 V
F1-30 (IAC1) - F4-1 (E1) B - BR Swirl control valve position sensor Engine switch off to on (IG) 3.0 to 4.0 V
F3-7 (IA1+) - F2-2 (E01) LG - W-B Intake air control valve actuator for swirl control valve Idling with cold engine

Pulse generation

(see waveform 15)
F3-6 (IA1-) - F2-2 (E01) B - W-B Intake air control valve actuator for swirl control valve Idling with cold engine

Pulse generation

(see waveform 16)
A21-24 (STJ1) - F4-1 (E1) GR - BR Cold start injector Engine switch on (IG) 11 to 14 V
A19-19 (RFC) - F4-1 (E1) GR - BR Cooling fan control signal

Engine switch on (IG)

A/C switch on (Max cool)

Pulse generation

(see waveform 19)
A21-14 (CANH) - F4-1 (E1) G - BR CAN communication line Engine switch on (IG)

Pulse generation

(see waveform 17)
A21-13 (CANL) - F4-1 (E1) W - BR CAN communication line Engine switch on (IG)

Pulse generation

(see waveform 18)
A19-1 (EC) - Body ground W-B - - Ground Always Below 1 Ω

Tech Tips

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

*2: for LHD

*3: for RHD


  1. WAVEFORM 1

    A01FF3FE01
    Camshaft timing oil control valve assembly operation signal
    ECM Terminal Name

    Between OC1+ and OC1- or OC2+ and OC2-

    Between OE1+ and OE1- or OE2+ and OE2-
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling

  2. WAVEFORM 2

    A01FDG3E01
    Air fuel ratio sensor heater operation signal
    ECM Terminal Name Between HA1A and E04 or HA2A and E05
    Tester Range 5 V/DIV., 10 ms./DIV.
    Condition Idling

  3. WAVEFORM 3

    A01FEZLE15
    Heated oxygen sensor signal
    ECM Terminal Name Between OX1B and E2 or OX2B and E2
    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 Data List, item O2S B1S2 or O2S B2S2 shows the ECM input values from the heated oxygen sensor.

  4. WAVEFORM 4

    A01FEXPE01
    Knock sensor signal
    ECM Terminal Name

    Between KNK1 and EKNK

    Between KNK2 and EKN2
    Tester Range 1 V/DIV., 1 ms./DIV.
    Condition Engine speed maintained at 4000 rpm after warming up engine

    Tech Tips


    • The wavelength becomes shorter as the engine speed increases.

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

  5. WAVEFORM 5

    A01FGL7E01
    Crankshaft position sensor and VVT sensor for intake camshaft signal
    ECM Terminal Name

    Between NE+ and NE-

    Between VV1+ and VV1- or VV2+ and VV2-
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  6. WAVEFORM 6

    A01FEZUE01
    Crankshaft position sensor and VVT sensor for exhaust camshaft signal
    ECM Terminal Name

    Between NE+ and NE-

    Between EV1+ and EV1- or EV2+ and EV2-
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  7. WAVEFORM 7

    A01FH0CE06
    Igniter IGT Signal (from ECM to igniter) and Igniter IGF Signal (from igniter to ECM)
    ECM Terminal Name

    CH1: Between IGT (1 to 6) and E1

    CH2: Between IGF1 and E1 or IGF2 and E1
    Tester Range 2 V/DIV., 20 ms./DIV.
    Condition Idling

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  8. WAVEFORM 8

    A01FH6VE11
    Purge VSV operation signal
    ECM Terminal Name Between PRG and E1
    Tester Range 10 V/DIV., 20 ms./DIV.
    Condition Idling

    Tech Tips

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

  9. WAVEFORM 9

    A01FG4FE01
    Vehicle speed signal
    ECM Terminal Name Between SPD and E1
    Tester Range 2 V/DIV., 20 ms./DIV.
    Condition Driving at 20 km/h (12 mph)

    Tech Tips

    The wavelength becomes shorter as the vehicle speed increases.

  10. WAVEFORM 10

    A01FIPHE03
    Throttle actuator positive terminal
    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.

  11. WAVEFORM 11

    A01FGTWE01
    Throttle actuator negative terminal
    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.

  12. WAVEFORM 12

    A01FGQ5E01
    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 speed increases.

  13. WAVEFORM 13

    A01FEIQE10
    Fuel Injector No. 1 (to No. 6) Injection Signal and Injection Confirmation Signal
    ECM Terminal Name

    CH1: Between #1 or #4 and E1

    CH2: Between INJ1 and E1

    CH1: Between #2 or #5 and E1

    CH2: Between INJ2 and E1

    CH1: Between #3 or #6 and E1

    CH2: Between INJ3 and E1
    Tester Range 2 V/DIV., 20 ms./DIV.
    Condition Idling

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  14. WAVEFORM 14

    A01FFK8E01
    High pressure side fuel pump (Spill control valve)
    ECM Terminal Name

    CH1: Between FPD and E1

    CH2: Between FPF1 and E1
    Tester Range 2 V/DIV., 5 ms./DIV.
    Condition Idling

  15. WAVEFORM 15

    A01FI89E14
    Intake air control valve actuator for swirl control valve positive terminal
    ECM Terminal Name Between IA1+ and E01
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling with cold engine

  16. WAVEFORM 16

    A01FFUXE13
    Intake air control valve actuator for swirl control valve negative terminal
    ECM Terminal Name Between IA1- and E01
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling with cold engine

  17. WAVEFORM 17

    A01FF50E04
    CAN communication signal
    ECM Terminal Name Between CANH and E1
    Tester Range 1 V/DIV., 10 μs./DIV.
    Condition Engine switch on (IG)

    Tech Tips

    The waveform varies depending on the CAN communication signal.

  18. WAVEFORM 18

    A01FG35E05
    CAN communication signal
    ECM Terminal Name Between CANL and E1
    Tester Range 1 V/DIV., 10 μs./DIV.
    Condition Engine switch on (IG)

    Tech Tips

    The waveform varies depending on the CAN communication signal.

  19. WAVEFORM 19

    A01FGMUE01
    Cooling Fan Control Signal
    Hybrid Vehicle Control ECU Terminal Name Between RFC and E1
    Tester Range 1 V/DIV., 20 ms./DIV.
    Condition Engine switch on (IG), A/C switch on (max cool)

    Tech Tips

    The wavelength becomes shorter as the engine coolant temperature.