SFI SYSTEM TERMINALS OF ECM

A01DZF5E02

Tech Tips

Each ECM terminal's standard normal voltage is shown in the table below.

In the table, first check the information under "Condition". Look under "Symbols (Terminal No.)" for the terminals to be inspected. The standard voltage between the terminals is shown under "Specified Condition".

Use the illustration above as a reference for the ECM terminals.

Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
BATT (E9-3) - E1 (E12-3) L - BR Battery (for measuring battery voltage and for ECM memory) Always 9 to 14 V
+BM (E9-7) - E1 (E12-3) R-W - BR Power source of throttle motor Always 9 to 14 V
IGSW (E9-9) - E1 (E12-3) B-O - BR Ignition switch Ignition switch ON 9 to 14 V
+B (E9-1) - E1 (E12-3) B - BR Power source of ECM Ignition switch ON 9 to 14 V
MREL (E9-8) - E1 (E12-3) W-G - BR EFI relay Ignition switch ON 9 to 14 V
VC (E12-18) - E2 (E12-28) LG-B - BR Power source of sensor (specific voltage) Ignition switch ON 4.5 to 5.5 V
VTA1 (E12-20) - E2 (E12-28) B-R - BR Throttle position sensor (for engine control) Ignition switch ON, accelerator pedal fully released 0.5 to 1.1 V
VTA1 (E12-20) - E2 (E12-28) B-R - BR Throttle position sensor (for engine control) Ignition switch ON, accelerator pedal fully depressed 3.2 to 4.8 V
VTA2 (E12-19) - E2 (E12-28) LG - BR Throttle position sensor (for sensor malfunction detection) Ignition switch ON, accelerator pedal fully released 2.1 to 3.1 V
VTA2 (E12-19) - E2 (E12-28) LG - BR Throttle position sensor (for sensor malfunction detection) Ignition switch ON, accelerator pedal fully depressed 4.5 to 5.5 V
VPA (E9-18) - EPA (E9- 20) W-L - BR-W Accelerator pedal position sensor (for engine control) Ignition switch ON, accelerator pedal fully released 0.5 to 1.1 V
VPA (E9-18) - EPA (E9- 20) W-L - BR-W Accelerator pedal position sensor (for engine control) Ignition switch ON, accelerator pedal fully depressed 2.5 to 4.6 V
VPA2 (E9-19) - EPA2 (E9-21) GR-G - BR-Y Accelerator pedal position sensor (for sensor malfunction detection) Ignition switch ON, accelerator pedal fully released 1.5 to 2.9 V
VPA2 (E9-19) - EPA2 (E9-21) GR-G - BR-Y Accelerator pedal position sensor (for sensor malfunction detection) Ignition switch ON, accelerator pedal fully depressed 3.5 to 5.5 V
VCPA (E9-26) - EPA (E9-20) LG-R - BR-W Power source of accelerator pedal position sensor (for VPA) Ignition switch ON 4.5 to 5.5 V
VCP2 (E9-27) - EPA2 (E9-21) BR-R - BR-Y Power source of accelerator pedal position sensor (for VPA2) Ignition switch ON 4.5 to 5.5 V
VG (E11-28) - E2G (E11-30) L-W - L-R MAF meter Idling, shift position on P or N (for A/T) or neutral (for M/T), A/C switch off 0.5 to 3.0 V
THA (E11-29) - E2 (E12-28) L-B - BR IAT sensor Idling, intake air temperature 20°C (68°F) 0.5 to 3.4 V
THW (E12-32) - E2 (E12-28) B - BR ECT sensor Idling, engine coolant temperature 80°C (176°F) 0.2 to 1.0 V

#10 (E11-6) - E01 (E12-7)

#20 (E11-5) - E01 (E12-7)

#30 (E11-2) - E01 (E12-7)

#40 (E11-1) - E01 (E12-7)

L - W-B

G - W-B

R - W-B

W - W-B

 Injector Ignition switch ON 9 to 14 V

#10 (E11-6) - E01 (E12-7)

#20 (E11-5) - E01 (E12-7)

#30 (E11-2) - E01 (E12-7)

#40 (E11-1) - E01 (E12-7)

L - W-B

G - W-B

R - W-B

W - W-B

 Injector Idling Pulse generation (see waveform 6)

IGT1 (E12-17) - E1 (E12-3)

IGT2 (E12-16) - E1 (E12-3)

IGT3 (E12-15) - E1 (E12-3)

IGT4 (E12-14) - E1 (E12-3)

R - BR

R-L - BR

G-B - BR

G - BR

 Ignition coil with igniter ignition signal Idling Pulse generation (see waveform 5)
IGF1 (E12-23) - E1 (E12-3) G-R - BR Ignition coil with igniter (ignition confirmation signal) Ignition switch ON 4.5 to 5.5 V
IGF1 (E12-23) - E1 (E12-3) G-R - BR Ignition coil with igniter (ignition confirmation signal) Idling Pulse generation (see waveform 5)
G2+ (E12-26) - NE- (E12-34) R - G Camshaft position sensor Idling Pulse generation (see waveform 3)
NE+ (E12-27) - NE- (E12-34) L - G Crankshaft position sensor Idling Pulse generation (see waveform 3)
FC (E9-25) - E01 (E12-7) LG-B - W-B Fuel pump control Ignition switch ON 9 to 14 V
A1A+ (E12-21)*3 - E1 (E12-3) B - BR A/F sensor Always (Ignition switch ON) Fixed at 3.3 V *1
A1A- (E12-31)*3 - E1 (E12-3) W - BR A/F sensor Always (Ignition switch ON) Fixed at 3.3 V *1
HA1A (E12-1)*3 - E04 (E11-7) Y - W-B A/F sensor heater Idling Below 3.0 V
HA1A (E12-1)*3 - E04 (E11-7) Y - W-B A/F sensor heater Ignition switch ON 9 to 14 V
OX1A (E12-21)*5 - E2 (E12-28) B -BR Heated oxygen sensor Maintain engine speed at 2,500 rpm for 2 minutes after warming up sensor Pulse generation (see waveform 12)
OX1B (E12-25)*3 - E2 (E12-28) B - BR Heated oxygen sensor Maintain engine speed at 2,500 rpm for 2 minutes after warming up sensor Pulse generation (see waveform 9)
HT1A (E12-1)*5 - E03 (E11-4) W - B Heated oxygen sensor heater Ignition switch ON 9 to 14 V
HT1B (E12-2)*3 - E03 (E11-4) L-Y - W-B Heated oxygen sensor heater Idling Below 3.0 V
HT1B (E12-2)*3 - E03 (E11-4) L-Y - W-B Heated oxygen sensor heater Ignition switch ON 9 to 14 V
M+ (E12-5) - ME01 (E11-3) B - W-B Throttle actuator Idling Pulse generation (see waveform 1)
M- (E12-4) - ME01 (E11-3) W - W-B Throttle actuator Idling Pulse generation (see waveform 2)
KNK1 (E12-29) - EKNK (E12-30) B - W Knock sensor Maintain engine speed at 4,000 rpm after warming up engine Pulse generation (see waveform 8)
OC1+ (E12-13) - OC1- (E12-12) P-L - Y Camshaft timing oil control valve Ignition switch ON Pulse generation (see waveform 7)
PRG (E11-23)*6 - E01 (E12-7) L - W-B VSV for EVAP Ignition switch ON 9 to 14 V
PRG (E11-23)*6 - E01 (E12-7) L - W-B VSV for EVAP Idling Pulse generation (see waveform 10)
STA (E9-12) - E1 (E12-3)

L-Y*9 - BR

B-Y*8 - BR

 Starter signal Shift position on P or N (for A/T), or neutral (M/T), ignition switch START 6.0 V or more
ALT (E12-10) - E1 (E12-3) G - BR Generator Ignition switch ON 9 to 14 V
STP (E10-4) - E1 (12-3) G-W - BR Stop light switch Brake pedal depressed 9 to 14 V
STP (E10-4) - E1 (12-3) G-W - BR Stop light switch Brake pedal released Below 1.5 V
ST1- (E9-16) - E1 (E12-3) R-L - BR Stop light switch Ignition switch ON, brake pedal depressed Below 1.5 V
ST1- (E9-16) - E1 (E12-3) R-L - BR Stop light switch Ignition switch ON, brake pedal released 7.5 to 14 V
W (E10-30) - E1 (E12-3) R-B - BR MIL Idling 9 to 14 V
W (E10-30) - E1 (E12-3) R-B - BR MIL Ignition switch ON Below 3.0 V
ELS (E9-15) - E1 (E12-3) G - BR Electric load Taillight switch on 7.5 to 14 V
ELS (E9-15) - E1 (E12-3) G - BR Electric load Taillight switch off 0 to 1.5 V
ELS3 (E10-3)*7 - E1 (E12-3) B - BR Defogger Defogger switch ON 7.5 to 14 V
ELS3 (E10-3)*7 - E1 (E12-3) B - BR Defogger Defogger switch OFF 0 to 1.5 V
TACH (E10-1) - E1 (E12-3) B-W - BR Engine speed Idling Pulse generation
SPD (E10-8) - E1 (E12-3) V-R - BR Speed signal from combination meter Ignition switch ON, slowly turn wheel Pulse generation (see waveform 4)
TC (E10-17) - E1 (E12-3) P-B - BR Terminal TC of DLC3 Ignition switch ON 9 to 14 V
SIL (E10-13) - E1 (E12-3) R-Y - BR Terminal SIL of DLC3 Connect intelligent tester to DLC3 Pulse generation
PSW (E11-32) - E1 (E12-3) G-Y - BR Power steering oil pressure switch While turning steering wheel Below 1.5 V
F/PS (E10-32)*2 - E1 (E12-3) B - BR Center airbag sensor assembly center Ignition switch ON Pulse generation
AIRP (E12-11)*3 - E1 (E12-3) W-L - BR Air switching valve for secondary air injection system Idling 9 to 14 V
AIRV (E12-24)*3 - E1 (E12-3) V - BR Air pump control Idling 9 to 14 V
AIDI (E11-20)*3 - E1 (E12-3) G-W - BR Diagnostic information signal for air injection system Air injection system operates Pulse generation (see waveform 11)
VAF (E12-25)*4 - E1 (E12-3) G-B - BR Variable resistor Ignition switch ON 0 to 5.0 V
NSW (E9-30)*8 - E1 (E12- 3) L-Y - BR Park/Neutral switch signal Ignition switch ON and shift lever P or N position Below 1 V
NSW (E9-30)*8 - E1 (E12- 3) L-Y - BR Park/Neutral switch signal Ignition switch ON and shift lever except P and N 9 to 14 V

Tech Tips

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

*2: w/ Airbag

*3: w/ Secondary Air Injection

*4: Leaded gasoline specification vehicle

*5: Unleaded gasoline specification vehicle (w/o Secondary Air Injection)

*6: Unleaded gasoline specification vehicle

*7: w/ Rear window defogger

*8: for A/T

*9: for M/T


  1. Waveform 1 (Reference)

    A01DYXGE06
    Throttle actuator positive terminal
    Item Content
    Symbols (Terminal No.) M+ (E12-5) - ME01 (E11-3)
    Tool Setting 5 V/DIV., 1 msec./DIV.
    Condition Idle after engine warm-up

    Tech Tips

    The duty ratio varies depending on the throttle opening operation.

  2. Waveform 2 (Reference)

    A01DYF2E04
    Throttle actuator negative terminal
    Item Content
    Symbols (Terminal No.) M- (E12-4) - ME01 (E11-3)
    Tool Setting 5 V/DIV., 1 msec./DIV.
    Condition Idle after engine warm-up

    Tech Tips

    The duty ratio varies depending on the throttle opening operation.

  3. Waveform 3 (Reference)

    A01DYMIE01
    (a) Camshaft position sensor
    Item Content
    Symbols (Terminal No.) (a) G2+ (E12-26) - NE- (E12-34)
    Tool Setting 5 V/DIV., 20 msec./DIV.
    Condition Idle after engine warm-up
    (b) Crankshaft position sensor
    Item Content
    Symbols (Terminal No.) (b) NE+ (E12-27) - NE- (E12-34)
    Tool Setting 5 V/DIV., 20 msec./DIV.
    Condition Idle after engine warm-up

    Tech Tips

    The wavelength becomes shorter as engine speed increases.

  4. Waveform 4 (Reference)

    A01DYU9E01
    Vehicle speed signal
    Item Content
    Symbols (Terminal No.) SPD (E10-8) - E1 (E12-3)
    Tool Setting 2 V/DIV., 10 msec./DIV.
    Condition Driving at 40 km/h (25 mph)

    Tech Tips

    The wavelength becomes shorter as vehicle speed increases.

  5. Waveform 5 (Reference)

    A01DZ0ZE01
    (a) Igniter IGT signal (from ECM to igniter)
    Item Content
    Symbols (Terminal No.) (a) IGT1 (E12-17) to IGT4 (E12-14) - E1 (E12-3)
    Tool Setting 2 V/DIV., 20 msec./DIV.
    Condition Idling
    (b) Igniter IGF signal (from igniter to ECM)
    Item Content
    Symbols (Terminal No.) (b) IGF1 (E12-23) - E1 (E12-3)
    Tool Setting 2 V/DIV., 20 msec./DIV.
    Condition Idling

    Tech Tips

    The wavelength becomes shorter as engine speed increases.

  6. Waveform 6 (Reference)

    A01DYB8E01
    Fuel injector
    Item Content
    Symbols (Terminal No.) #10 (E11-6) to #40 (E11-1) - E01 (E12-7)
    Tool Setting 20 V/DIV., 20 msec./DIV.
    Condition Idling

    Tech Tips

    The wavelength becomes shorter as engine speed increases.

  7. Waveform 7 (Reference)

    A01E34IE01
    VVT OCV
    Item Content
    Symbols (Terminal No.) OC1+ (E12-13) - OC1- (E12-12)
    Tool Setting 5 V/DIV., 1 msec./DIV.
    Condition Accelerate slowly after engine warm-up

    Tech Tips

    VVT OCV DUTY (%) = A/B x 100

  8. Waveform 8 (Reference)

    A01E0OGE01
    Knock sensor
    Item Content
    Symbols (Terminal No.) KNK1 (E12-29) - EKNK (E12-30)
    Tool Setting 0.01 to 10 V/DIV., 0.01 to 10 msec./DIV.
    Condition After warming up engine, keep engine speed at 4,000 rpm

    Tech Tips


    • The wavelength becomes shorter as engine speed increases.

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

  9. Waveform 9 (Reference)

    A01E1HTE08
    Heated oxygen (HO2) sensor (sensor 2)
    Item Content
    Symbols (Terminal No.) OX1B (E12-25) - E2 (E12-28)
    Tool Setting 0.2 V/DIV., 200 msec./DIV.
    Condition Engine maintained at 2,500 rpm when engine warmed up

    Tech Tips

    In the Data List, item O2S B1 S2 shows the ECM input values from the rear HO2 sensor (sensor 2).

  10. Waveform 10 (Reference)

    A01DWZ0E01
    Purge VSV
    Item Content
    Symbols (Terminal No.) PRG (E11-23) - E01 (E12-7)
    Tool Setting 10 V/DIV., 20 msec./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.

  11. Waveform 11 (Reference)

    A01DV09E01
    Terminal DI of air injection control driver
    Item Content
    Symbols (Terminal No.) AIDI (E11-20) - E1 (E12-3)
    Tool Setting 5 V/DIV., 50 msec./DIV.
    Condition Air injection system operates

    Tech Tips

    The wavelength changes when the air injection control driver detects malfunction in the air injection system Click here

  12. Waveform 12 (Reference)

    A01DZEHE11
    Heated oxygen (HO2) sensor (sensor 1)
    Item Content
    Symbols (Terminal No.) OX1A (E12-21) - E2 (E12-28)
    Tool Setting 0.2 V/DIV., 200 msec./DIV.
    Condition Engine maintained at 2,500 rpm when engine warmed up

    Tech Tips

    In the Data List, item O2S B1 S1 shows the ECM input values from the rear HO2 sensor (sensor 1).