SFI SYSTEM(w/o Canister Pump Module) TERMINALS OF ECM

B004QN7E27

Tech Tips

The standard voltage, resistance and waveform between each pair of the ECM terminals is shown in the table below. The appropriate conditions for checking each pair of the terminals is also indicated. The result of checks should be compared with the standard voltage, resistance and waveform for each pair of the terminals as 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
A40-1 (BATT) - C31-59 (E1) B - W-B Auxiliary battery (for measuring auxiliary battery voltage and for ECM memory) Power switch off 11 to 16 V
A40-2 (+B) - C31-59 (E1) R - W-B Power source of ECM Engine stopped, power switch on (IG) 11 to 14 V
A40-3 (+B2) - C31-59 (E1) R - W-B Power source of ECM Engine stopped, power switch on (IG) 11 to 14 V
A40-6 (IGSW) - C31-59 (E1) BE - W-B Power switch signal Engine stopped, power switch on (IG) 11 to 14 V
A40-7 (FANL) - C31-59 (E1) R - W-B Cooling fan motor operation signal (low) Power switch on (IG) 11 to 14 V
Idling, high engine coolant temperature Below 1.5 V
A40-8 (FANH) - C31-59 (E1) LG - W-B Cooling fan motor operation signal (high) Power switch on (IG) 11 to 14 V
Idling, high engine coolant temperature Below 1.5 V
A40-13 (CANH) - C31-59 (E1) R - W-B CAN communication line Engine stopped, power switch on (IG)

Pulse generation

(See waveform 1)
A40-26 (CANL) - C31-59 (E1) W - W-B CAN communication line Engine stopped, power switch on (IG)

Pulse generation

(See waveform 2)
A40-30 (NEO) - C31-59 (E1) L - W-B Crankshaft revolution signal Idling with warm engine

Pulse generation

(See waveform 3)
A40-31 (TACH) - C31-59 (E1) V - W-B Engine speed signal Idling with warm engine

Pulse generation

(See waveform 4)
A40-32 (EC) - Body ground W-B - - Ground Always Below 1 Ω
A40-41 (FC) - C31-59 (E1) SB - W-B Fuel pump control Engine stopped, power switch on (IG) 11 to 14 V
Idling Below 1.5 V
A40-42 (FUEL) - C31-59 (E1) P - W-B Fuel lid opener switch signal Fuel lid opener switch pressed Below 1.0 V
Fuel lid opener switch not pressed 11 to 14 V
A40-46 (MREL) - C31-59 (E1) G - W-B EFI-MAIN relay operation signal Engine stopped, power switch on (IG) 11 to 14 V
A40-59 (FREL) - C31-59 (E1) LG - W-B Fuel lid lock with motor assembly operation signal Fuel lid lock with motor assembly operating Below 1.0 V
Fuel lid lock with motor assembly not operating 11 to 14 V
C31-26 (E04) - Body ground W-B - - Ground Always Below 1 Ω
C31-27 (HA1A) - C31-26 (E04) R - W-B Air fuel ratio sensor heater operation signal Engine stopped, power switch on (IG) 11 to 14 V
Idling with cold engine

Pulse generation

(See waveform 5)
C31-28 (ME01) - Body ground W-B - - Ground Always Below 1 Ω
C31-29 (+BM) - C31-59 (E1) R - W-B Power source of throttle actuator Power switch off 11 to 16 V
C31-30 (M-) - C31-28 (ME01) P - W-B Throttle actuator operation signal (negative signal) Idling with warm engine

Pulse generation

(See waveform 6)
C31-31 (CAN+) - C31-59 (E1) SB - W-B CAN communication line Engine stopped, power switch on (IG)

Pulse generation

(See waveform 1)
C31-32 (CAN-) - C31-59 (E1) W - W-B CAN communication line Engine stopped, power switch on (IG)

Pulse generation

(See waveform 2)
C31-33 (PRG) - C31-59 (E1) V - W-B Purge VSV operation signal Engine stopped, power switch on (IG) 11 to 14 V
Idling with warm engine, under purge control

Pulse generation

(See waveform 7)
C31-35 (OC1+) - C31-34 (OC1-) L - G Camshaft timing oil control valve assembly operation signal Idling

Pulse generation

(See waveform 8)
C31-56 (HT1B) - C31-26 (E04) G - W-B Heated oxygen sensor heater operation signal Engine stopped, power switch on (IG) 11 to 14 V
Idling with cold engine Below 3.0 V
C31-57 (E01) - Body ground W-B - - Ground Always Below 1 Ω
C31-58 (E02) - Body ground W-B - - Ground Always Below 1 Ω
C31-59 (E1) - Body ground W-B - - Ground Always Below 1 Ω
C31-60 (M+) - C31-28 (ME01) V - W-B Throttle actuator operation signal (positive terminal) Idling with warm engine

Pulse generation

(See waveform 9)
C31-62 (WSV)*1 - C31-59 (E1) G - W-B Flow shutting valve (water valve) operation signal Engine stopped, power switch on (IG) 11 to 14 V
C31-68 (WPI) - C31-59 (E1) P - W-B Engine water pump assembly signal Idling with warm engine

Pulse generation

(See waveform 10)
C31-69 (WPO) - C31-59 (E1) L - W-B Engine water pump assembly signal Idling with warm engine

Pulse generation

(See waveform 11)
C31-70 (G2O) - C31-59 (E1) W - W-B Camshaft revolution signal Idling with warm engine

Pulse generation

(See waveform 12)
C31-71 (IGF1) - C31-59 (E1) L - W-B

Ignition coil assembly signal

(ignition confirmation signal)

 Power switch on (IG) 4.5 to 5.5 V
Idling with warm engine

Pulse generation

(See waveform 13)
C31-72 (IGT4) - C31-59 (E1) V - W-B

No. 4 ignition coil assembly signal

(ignition signal)

 Idling with warm engine

Pulse generation

(See waveform 13)
C31-73 (IGT3) - C31-59 (E1) G - W-B

No. 3 ignition coil assembly signal

(ignition signal)

 Idling with warm engine

Pulse generation

(See waveform 13)
C31-74 (IGT2) - C31-59 (E1) B - W-B

No. 2 ignition coil assembly signal

(ignition signal)

 Idling with warm engine

Pulse generation

(See waveform 13)
C31-75 (IGT1) - C31-59 (E1) GR - W-B

No. 1 ignition coil assembly signal

(ignition signal)

 Idling with warm engine

Pulse generation

(See waveform 13)
C31-77 (VCPM) - C31-76 (EPIM) GR - V Power source of manifold absolute pressure sensor Engine stopped, power switch on (IG) 4.75 to 5.25 V
C31-78 (PIM) - C31-76 (EPIM) B - V Manifold absolute pressure sensor signal Engine stopped, power switch on (IG) 3.0 to 4.5 V
C31-82 (VV1+) - C31-115 (VV1-) SB - W Camshaft position sensor signal Idling with warm engine

Pulse generation

(See waveform 14)
C31-95 (#20) - C31-57 (E01) LG - W-B No. 2 fuel injector assembly signal Idling with warm engine

Pulse generation

(See waveform 15)
C31-96 (#30) - C31-57 (E01) L - W-B No. 3 fuel injector assembly signal Idling with warm engine

Pulse generation

(See waveform 15)
C31-97 (#40) - C31-57 (E01) R - W-B No. 4 fuel injector assembly signal Idling with warm engine

Pulse generation

(See waveform 15)
C31-98 (#10) - C31-57 (E01) BE - W-B No. 1 fuel injector assembly signal Idling with warm engine

Pulse generation

(See waveform 15)
C31-99 (OX1B) - C31-131 (EX1B) V - P Heated oxygen sensor signal Engine speed maintained at 2500 rpm for 2 minutes after warming up engine

Pulse generation

(See waveform 16)
C31-100 (A1A+) - C31-59 (E1) Y - W-B Air fuel ratio sensor signal Engine stopped, power switch on (IG) 3.0 to 3.6 V*2
C31-101 (VTA2) - C31-133 (ETA) B - G Throttle position sensor signal (for sensor malfunction detection) Engine stopped, power switch on (IG), accelerator pedal fully released 2.1 to 3.1 V
C31-105 (EGR4) - C31-59 (E1) LG - W-B EGR valve assembly signal EGR valve assembly operating

Pulse generation

(See waveform 17)
C31-106 (EGR2) - C31-59 (E1) R - W-B EGR valve assembly signal EGR valve assembly operating

Pulse generation

(See waveform 17)
C31-107 (EGR3) - C31-59 (E1) BE - W-B EGR valve assembly signal EGR valve assembly operating

Pulse generation

(See waveform 17)
C31-108 (GE01) - Body ground L - - Shielded (ground) circuit of throttle actuator Always Below 1 Ω
C31-114 (NE+) - C31-113 (NE-) B - W Crankshaft position sensor signal Idling with warm engine

Pulse generation

(See waveform 18)
C31-116 (VCV1) - C31-59 (E1) R - W-B Power source of camshaft position sensor Engine stopped, power switch on (IG) 4.5 to 5.5 V
C31-120 (THW) - C31-119 (ETHW) L - BR Engine coolant temperature sensor signal Idling, engine coolant temperature 75 to 100°C (167 to 212°F) 0.2 to 1.0 V
C31-122 (KNK1) - C31-121 (EKNK) B - W Knock control sensor signal Engine speed maintained at 2500 rpm after warming up engine

Pulse generation

(See waveform 19)
C31-129 (THHW)*1 - C31-130 (ETHH)*1 P - BR No. 2 engine coolant temperature sensor signal Idling, engine coolant temperature 75 to 100°C (167 to 212°F) 0.2 to 1.0 V
C31-132 (A1A-) - C31-59 (E1) BR - W-B Air fuel ratio sensor signal Engine stopped, power switch on (IG) 2.7 to 3.3 V*2
C31-134 (VCTA) - C31-133 (ETA) R - G Power source of throttle position sensor (specific voltage) Engine stopped, power switch on (IG) 4.5 to 5.5 V
C31-135 (VTA1) - C31-133 (ETA) BE - G Throttle position sensor signal (for engine control) Engine stopped, power switch on (IG), accelerator pedal fully released 0.6 to 1.1 V
C31-137 (VG) - C31-104 (E2G) G - L Mass air flow meter sub-assembly signal Idling, park (P) or neutral (N) selected, A/C switch off 0.5 to 3.0 V
C31-138 (THA) - C31-139 (ETHA) V - GR Intake air temperature sensor (mass air flow meter sub-assembly) signal Idling, intake air temperature 0 to 80°C (32 to 176°F) 0.5 to 3.4 V
C31-140 (EGR1) - C31-59 (E1) P - W-B EGR valve assembly signal EGR valve assembly operating

Pulse generation

(See waveform 17)


  1. WAVEFORM 1

    B004QTUE01
    *a 1 V/DIV.
    *b 10 μs./DIV.
    CAN Communication Signal (Reference)
    ECM Terminal Name

    Between CANH and E1

    Between CAN+ and E1
    Tester Range 1 V/DIV., 10 μs./DIV.
    Condition Engine stopped, power switch on (IG)

    Tech Tips

    The waveform varies depending on the CAN communication signal.

  2. WAVEFORM 2

    B004P6AE01
    *a 1 V/DIV.
    *b 10 μs./DIV.
    CAN Communication Signal (Reference)
    ECM Terminal Name

    Between CANL and E1

    Between CAN- and E1
    Tester Range 1 V/DIV., 10 μs./DIV.
    Condition Engine stopped, power switch on (IG)

    Tech Tips

    The waveform varies depending on the CAN communication signal.

  3. WAVEFORM 3

    B004OGUE27
    *a 5 V/DIV.
    *b 20 ms./DIV.
    Crankshaft Revolution Signal from ECM to Inverter with Converter Assembly
    ECM Terminal Name Between NEO and E1
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  4. WAVEFORM 4

    B004OXPE07
    *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 with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  5. WAVEFORM 5

    B004QW4E04
    *a 5 V/DIV.
    *b 10 ms./DIV.
    Air Fuel Ratio Sensor Heater Operation Signal
    ECM Terminal Name Between HA1A and E04
    Tester Range 5 V/DIV., 10 ms./DIV.
    Condition Idling with cold engine

  6. WAVEFORM 6

    B004QM4E22
    *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.

  7. WAVEFORM 7

    B004OUDE05
    *1 10 V/DIV.
    *2 20 ms./DIV.
    Purge VSV Operation Signal
    ECM Terminal Name Between PRG and E1
    Tester Range 10 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine, under purge control

    Tech Tips

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

  8. WAVEFORM 8

    B004PL3E01
    *a 5 V/DIV.
    *b 1 ms./DIV.
    Camshaft Timing Oil Control Valve Assembly Operation Signal
    ECM Terminal Name Between OC1+ and OC1-
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling

  9. WAVEFORM 9

    B004ORTE20
    *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.

  10. WAVEFORM 10

    B004OGUE24
    *a 5 V/DIV.
    *b 20 ms./DIV.
    Engine Water Pump Assembly Signal (from Engine Water Pump Assembly to ECM)
    ECM Terminal Name Between WPI and E1
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine water pump speed increases.

  11. WAVEFORM 11

    B004OGUE24
    *a 5 V/DIV.
    *b 20 ms./DIV.
    Engine Water Pump Assembly Signal (from ECM to Engine Water Pump Assembly)
    ECM Terminal Name Between WPO and E1
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine water pump speed increases.

  12. WAVEFORM 12

    B004OGUE25
    *a 5 V/DIV.
    *b 20 ms./DIV.
    Camshaft Revolution Signal from ECM to Inverter with Converter Assembly
    ECM Terminal Name Between G2O and E1
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  13. WAVEFORM 13

    B004Q9DE05
    *a 2 V/DIV.
    *b 20 ms./DIV.
    Ignition Coil Assembly Signal (IGT and IGF Signal)
    ECM Terminal Name

    CH1: Between IGT (1 to 4) and E1

    CH2: Between IGF1 and E1
    Tester Range 2 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  14. WAVEFORM 14

    B004Q9BE02
    *a 5 V/DIV.
    *b 20 ms./DIV.
    Camshaft Position Sensor Signal
    ECM Terminal Name Between VV1+ and VV1-
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  15. WAVEFORM 15

    B004PSBE11
    *1 20 V/DIV.
    *2 20 ms./DIV.
    No. 1 (to No. 4) Fuel Injector Assembly Signal
    ECM Terminal Name Between #10 (to #40) and E01
    Tester Range 20 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  16. WAVEFORM 16

    B004P0WE01
    *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

    Data List item "O2 Sensor Voltage B1S2" shows the ECM values from the heated oxygen sensor.

  17. WAVEFORM 17

    B004OHJE05
    *1 20 V/DIV.
    *2 50 ms./DIV.
    EGR Valve Assembly Signal
    ECM Terminal Name Between EGR1 ( to EGR4) and E1
    Tester Range 20 V/DIV., 50 ms./DIV.
    Condition EGR valve assembly operating

  18. WAVEFORM 18

    B004PIAE10
    *a 5 V/DIV.
    *b 20 ms./DIV.
    Crankshaft Position Sensor Signal
    ECM Terminal Name Between NE+ and NE-
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  19. WAVEFORM 19

    B004OIDE01
    *a 1 V/DIV.
    *b 1 ms./DIV.
    Knock Control Sensor Signal
    ECM Terminal Name Between KNK1 and EKNK
    Tester Range 1 V/DIV., 1 ms./DIV.
    Condition Engine speed maintained at 2500 rpm after warming up engine

    Tech Tips


    • The wavelength becomes shorter as the engine speed increases.

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