SFI SYSTEM TERMINALS OF ECM

A0054N9E02

Tech Tips

The standard 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 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
A40-20 (BATT) - B39-105 (E1) P - BR Battery (for measuring battery voltage and for ECM memory) Always 11 to 14 V
A40-2 (+B) - B39-105 (E1) B - BR Power source of ECM Ignition switch ON with engine stopped 11 to 14 V
A40-1 (+B2) - B39-105 (E1) B - BR Power source of ECM Ignition switch ON with engine stopped 11 to 14 V
A40-3 (+BM) - B39-105 (E1) B - BR Power source of throttle actuator Always 11 to 14 V
B39-109 (IGT1) - B39-105 (E1) W-L - BR

Ignition coil assembly

(ignition signal)

 Idling with warm engine

Pulse generation

(See waveform 1)
B39-108 (IGT2) - B39-105 (E1) B - BR
B39-107 (IGT3) - B39-105 (E1) L-B - BR
B39-106 (IGT4) - B39-105 (E1) B - BR
B39-82 (IGF1) - B39-105 (E1) Y - BR

Ignition coil assembly

(ignition confirmation signal)

 Ignition switch ON 4.5 to 5.5 V
Idling with warm engine

Pulse generation

(See waveform 1)
B39-93 (NE+) - B39-117 (NE-) B - W Crankshaft position sensor Idling with warm engine

Pulse generation

(See waveform 2)
B39-94 (G2+) - B39-118 (G2-) G - Y Camshaft position sensor (intake side) Idling with warm engine

Pulse generation

(See waveform 2)
B39-86 (#10) - B39-46 (E01) V - BR Fuel injector assembly Ignition switch ON 11 to 14 V
B39-85 (#20) - B39-46 (E01) Y - BR Idling with warm engine

Pulse generation

(See waveform 3)
B39-84 (#30) - B39-46 (E01) G - BR
B39-83 (#40) - B39-46 (E01) LG - BR
B39-104 (HA1A) - B39-41 (E04) R - W-B Air fuel ratio sensor heater (sensor 1) Ignition switch ON 11 to 14 V
Idling before air fuel ratio sensor warms up

Pulse generation

(See waveform 15)
B39-103 (A1A+) - B39-105 (E1) L - BR Air fuel ratio sensor (sensor 1) Ignition switch ON 3.0 V*1
B39-126 (A1A-) - B39-105 (E1) P - BR Air fuel ratio sensor (sensor 1) Ignition switch ON 3.3 V*1
B39-63 (HT1B) - B39-81 (E03) P - W-B Heated oxygen sensor heater (sensor 2) Ignition switch ON 11 to 14 V
Idling before heated oxygen sensor warms up Below 3.0 V
B39-80 (OX1B) - B39-79 (O1B-) BR - Y Heated oxygen sensor (sensor 2) Engine speed maintained at 2500 rpm for 2 minutes after heated oxygen sensor warms up

Pulse generation

(See waveform 4)
B39-110 (KNK1) - B39-111 (EKNK) G - R Knock control sensor Engine speed maintained at 4000 rpm after warming up

Pulse generation

(See waveform 5)
A40-38 (SPD) - B39-105 (E1) Y - BR Speed signal from combination meter assembly Vehicle being driven at approximately 20 km/h (12 mph)

Pulse generation

(See waveform 6)
B39-64 (THW) - B39-65 (ETHW) B - BR Engine coolant temperature sensor Engine coolant temperature 60 to 120°C (140 to 248°F) (while engine is warming up) 0.2 to 1.0 V
B39-87 (THA) - B39-88 (ETHA) P - BR-W Intake air temperature sensor Intake air temperature 0 to 80°C (32 to 176°F) (while engine is warming up) 0.5 to 3.4 V
B39-69 (VG) - B39-92 (E2G) V - R Mass air flow meter Idling with warm engine 0.5 to 3.0 V
A40-24 (W) - B39-105 (E1) P - BR MIL Engine coolant temperature sensor disconnected (MIL illuminated) Below 2.5 V
Idling with warm engine (MIL not illuminated) 11 to 14 V
A40-48 (STA) - B39-105 (E1) LG - BR Starter signal Cranking 5.5 V or higher
B39-113 (VTA1) - B39-90 (ETA) P - BR Throttle position sensor (for engine control) Ignition switch ON, throttle valve fully closed 0.5 to 1.1 V
Ignition switch ON, throttle valve fully open 3.2 to 4.8 V
B39-112 (VTA2) - B39-90 (ETA) R-G - BR Throttle position sensor (for sensor malfunction detection) Ignition switch ON, throttle valve fully closed 2.1 to 3.1 V
Ignition switch ON, throttle valve fully open 4.6 to 5.0 V
B39-89 (VCTA) - B39-90 (ETA) Y - BR Power source of throttle position sensor (fixed voltage) Idling with warm engine 4.5 to 5.5 V
A40-57 (VCPA) - A40-59 (EPA) P-L - R Power source of accelerator pedal position sensor (for VPA) Ignition switch ON with engine stopped 4.5 to 5.5 V
A40-55 (VPA) - A40-59 (EPA) L-W - R Accelerator pedal position sensor (for engine control) Accelerator pedal released (ignition switch ON with engine stopped) 0.5 to 1.1 V
Accelerator pedal fully depressed (ignition switch ON with engine stopped) 2.6 to 4.5 V
A40-56 (VPA2) - A40-60 (EPA2) Y - G Accelerator pedal position sensor (for sensor malfunction detection) Accelerator pedal released (ignition switch ON with engine stopped) 1.2 to 2.0 V
Accelerator pedal fully depressed (ignition switch ON with engine stopped) 3.4 to 5.0 V
A40-58 (VCP2) - A40-60 (EPA2) B - G Power source of accelerator pedal position sensor (for VPA2) Ignition switch ON with engine stopped 4.5 to 5.5 V
B39-43 (M+) - B39-44 (ME01) P - W-B Throttle actuator Idling with warm engine

Pulse generation

(See waveform 7)
B39-42 (M-) - B39-44 (ME01) L - W-B Throttle actuator Idling with warm engine

Pulse generation

(See waveform 8)
A40-36 (STP) - B39-105 (E1) V - BR Stop light switch assembly Stop light switch on (brake pedal depressed) 11 to 14 V
Stop light switch off (brake pedal released) Below 1.5 V
A40-35 (ST1-) - B39-105 (E1) R-L - BR Stop light switch assembly Stop light switch on (brake pedal depressed) Below 1.5 V
Stop light switch off (brake pedal released) 11 to 14 V
B39-62 (PRG) - B39-105 (E1) L-B - BR Purge VSV Ignition switch ON 11 to 14 V
Idling with warm engine

Pulse generation

(See waveform 9)
A40-19 (FC) - B39-105 (E1) R - BR Fuel pump control Ignition switch ON with engine stopped 11 to 14 V
Idling with warm engine Below 1.5 V
A40-15 (TACH) - B39-105 (E1) GR - BR Engine speed Idling with warm engine

Pulse generation

(See waveform 10)
A40-41 (TC) - B39-105 (E1) P - BR Terminal TC of DLC3 Ignition switch ON with engine stopped 11 to 14 V
B39-74 (OC1+) - B39-96 (OC1-) B - V Camshaft timing oil control valve (intake side) Idling with warm engine

Pulse generation

(See waveform 11)
A40-8 (CANH) - B39-105 (E1) Y - BR CAN communication line Ignition switch ON with engine stopped

Pulse generation

(See waveform 12)
A40-9 (CANL) - B39-105 (E1) W - BR CAN communication line Ignition switch ON with engine stopped

Pulse generation

(See waveform 13)
A40-27 (IGSW) - B39-105 (E1) B - BR Ignition switch Idling with warm engine 11 to 14 V
A40-44 (MREL) - B39-105 (E1) W - BR EFI MAIN relay Ignition switch ON with engine stopped 11 to 14 V
B39-75 (OE1+) - B39-97 (OE1-) BR - P Camshaft timing oil control valve (exhaust side) Idling with warm engine

Pulse generation

(See waveform 14)
B39-98 (EV1+) - B39-120 (EV1-) L - W Camshaft position sensor (exhaust side) Idling with warm engine

Pulse generation

(See waveform 2)
B39-119 (VCV1) - B39-105 (E1) BR-R - BR Power source for camshaft position sensor (fixed voltage) Idling with warm engine 4.5 to 5.5 V
B39-121 (VCE1) - B39-105 (E1) BR - BR Power source for camshaft position sensor (fixed voltage) Idling with warm engine 4.5 to 5.5 V
B39-52 (ALT) - B39-105 (E1) L - BR Generator Ignition switch ON 11 to 14 V
A40-43 (RFC) - B39-105 (E1) R-G - BR Cooling fan control Ignition switch ON 4.5 to 5.5 V
A40-39 (NEO) - B39-105 (E1)*2 P - BR Engine speed signal to power management control ECU Idling with warm engine

Pulse generation

(See waveform 16)
A40-25 (NSW) - B39-105 (E1) G - BR Park/neutral position switch Ignition switch ON, shift lever in P or N Below 1.5 V
Ignition switch ON, shift lever not in P or N 6.0 V or higher

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

*2: w/ Entry and Start System


  1. Waveform 1

    A0053KVE55
    *a 2 V/DIV.
    *b (IGT1 to 4)
    *c 20 ms./DIV.
    Ignition IGT Signal (from ECM to Ignition Coil Assembly)
    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 wavelengths become shorter as the engine speed increases.

  2. Waveform 2

    A0052YNE02
    *a 5 V/DIV.
    *b 20 ms./DIV.
    Crankshaft Position Sensor and Camshaft Position Sensors
    ECM Terminal Name

    CH1: Between G2+ and G2-

    CH1: Between EV1+ and EV1-

    CH2: Between NE+ and NE-
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelengths become shorter as the engine speed increases.

  3. Waveform 3

    A0055OYE01
    *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.

  4. Waveform 4

    A0055RUE01
    *1 0.2 V/DIV.
    *2 200 ms./DIV.
    Heated Oxygen Sensor (Sensor 2)
    ECM Terminal Name Between OX1B and O1B-
    Tester Range 0.2 V/DIV., 200 ms./DIV.
    Condition Engine speed maintained at 2500 rpm for 2 minutes after heated oxygen sensor warms up

    Tech Tips


    • The waveform shown may not appear.

    • The wavelength may vary.

  5. Waveform 5

    A00585HE01
    *a 1 V/DIV.
    *b 1 ms./DIV.
    Knock Control Sensor
    ECM Terminal Name Between KNK1 and EKNK
    Tester Range 1 V/DIV., 1 ms./DIV.
    Condition Engine speed maintained at 4000 rpm after warming up

    Tech Tips


    • The amplitude becomes larger as the engine speed increases.

    • The amplitude varies slightly depending on the vehicle.

  6. Waveform 6

    A0058I2E01
    *a 5 V/DIV.
    *b 20 ms./DIV.
    Vehicle Speed Signal
    ECM Terminal Name Between SPD and E1
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Vehicle being driven at approximately 20 km/h (12 mph)

    Tech Tips

    The wavelength becomes shorter as the vehicle speed increases.

  7. Waveform 7

    A0055HKE01
    *a 5 V/DIV.
    *b 1 ms./DIV.
    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 wavelength varies depending on the throttle valve opening angle.

  8. Waveform 8

    A0053WFE01
    *a 5 V/DIV.
    *b 1 ms./DIV.
    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 wavelength varies depending on the throttle valve opening angle.

  9. Waveform 9

    A00591OE02
    *1 10 V/DIV.
    *2 20 ms./DIV.
    Purge VSV
    ECM Terminal Name Between PRG and E1
    Tester Range 10 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    Tech Tips


    • The waveform shown may not appear.

    • The duty ratio may vary.

  10. Waveform 10

    A0058NPE01
    *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.

  11. Waveform 11

    A0057LWE01
    *a 5 V/DIV.
    *b 1 ms./DIV.
    Camshaft Timing Oil Control Valve for Intake Side
    ECM Terminal Name Between OC1+ and OC1-
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  12. Waveform 12

    A005378E02
    *a 1 V/DIV.
    *b 10 μsec./DIV.
    CAN Communication Signal
    ECM Terminal Name Between CANH and E1
    Tester Range 1 V/DIV., 10 μsec./DIV.
    Condition Ignition switch ON with engine stopped

  13. Waveform 13

    A0058F2E02
    *a 1 V/DIV.
    *b 10 μsec./DIV.
    CAN Communication Signal
    ECM Terminal Name Between CANL and E1
    Tester Range 1 V/DIV., 10 μsec./DIV.
    Condition Ignition switch ON with engine stopped

  14. Waveform 14

    A0057LWE01
    *a 5 V/DIV.
    *b 1 ms./DIV.
    Camshaft Timing Oil Control Valve for Exhaust Side
    ECM Terminal Name Between OE1+ and OE1-
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  15. Waveform 15

    A0057RIE01
    *a 5 V/DIV.
    *b 10 ms./DIV.
    Air Fuel Ratio Sensor Heater (Sensor 1)
    ECM Terminal Name Between HA1A and E04
    Tester Range 5 V/DIV., 10 ms./DIV.
    Condition Idling before air fuel ratio sensor warms up

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  16. Waveform 16

    A0057AM
    Engine speed signal
    ECM Terminal Name Between NEO and E1
    Tester Range 1 V/DIV., 2 ms./DIV.
    Condition Idling with warm engine