ECD SYSTEM TERMINALS OF ECM

B003Q1QE18

Tech Tips

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

In the table, first follow the information under "Condition". Look under "Terminal No. (Symbol)" 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.

Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
G50-1 (BATT) - C41-1 (E1) Y - W-B Battery (for measuring the battery voltage and for the ECM memory) Always 11 to 14 V
G50-18 (IGSW) - C41-1 (E1) GR - W-B Engine switch Engine switch on (IG) 11 to 14 V
G50-2 (+B) - C41-1 (E1) L - W-B Power source of ECM Engine switch on (IG) 11 to 14 V
G50-3 (+B2) - C41-1 (E1) B - W-B Power source of ECM Engine switch on (IG) 11 to 14 V
G50-4 (+B3) - C41-1 (E1) B - W-B Power source of ECM Engine switch on (IG) 11 to 14 V
G49-14 (MREL) - C41-1 (E1) W - W-B EFI-MAIN NO. 1 relay operation signal Engine switch on (IG) 11 to 14 V
10 seconds elapsed after engine switch off 0 to 1.5 V
C40-5 (+BD1) - C41-1 (E1) B - W-B EDU relay operation signal Engine switch on (IG) 11 to 14 V
C40-4 (+BD2) - C41-1 (E1) B - W-B EDU relay operation signal Engine switch on (IG) 11 to 14 V
G49-15 (GREL) - C41-1 (E1) LG - W-B GLOW relay Cranking 11 to 14 V
Idling (10 seconds or more after engine start) 0 to 1.5 V
G49-11 (NSW) - C41-1 (E1) L - W-B Park/Neutral position switch assembly signal Engine switch on (IG) , shift lever not in P or N 11 to 14 V
Engine switch on (IG) , shift lever in P or N Below 1.0 V
Clutch start switch signal Engine switch on (IG) , clutch pedal fully depressed Below 1.0 V
Engine switch on (IG) , clutch pedal released 11 to 14 V
G50-29 (VCPA) - G50-22 (EPA) LG - G Power source of accelerator pedal position sensor (for VPA) Engine switch on (IG) 4.5 to 5.5 V
G50-30 (VCP2) - G50-25 (EPA2) R - Y Power source of accelerator pedal position sensor (for VPA2) Engine switch on (IG) 4.5 to 5.5 V
G50-28 (VPA) - G50-22 (EPA) W - G Accelerator pedal position sensor signal (for engine control) Engine switch on (IG) , accelerator pedal fully released 0.5 to 1.1 V
Accelerator pedal position sensor signal (for engine control) Engine switch on (IG) , accelerator pedal fully depressed 3.0 to 4.6 V
G50-31 (VPA2) - G50-25 (EPA2) GR - Y Accelerator pedal position sensor signal (for sensor malfunction detection) Engine switch on (IG) , accelerator pedal fully released 0.9 to 2.3 V
Accelerator pedal position sensor signal (for sensor malfunction detection) Engine switch on (IG) , accelerator pedal fully depressed 3.4 to 5.0 V
C39-25 (VCVG) - C39-24 (EVG) L - Y Power source of mass air flow meter sub-assembly (for VG) Engine switch on (IG) 4.8 to 5.2 V
C39-33 (VG) - C39-24 (EVG) W - Y Mass air flow meter sub-assembly signal Engine switch on (IG)

Pulse generation

(See waveform 1)

C39-32 (THA) - C39-24 (EVG) B - Y Intake air temperature sensor (built into mass air flow meter sub-assembly) Idling, intake air temperature at 20°C (68°F) 0.5 to 3.4 V
C39-35 (THIA) - C39-27 (ETHI) G - BR Intake air temperature sensor (turbo) Idling, intake air temperature at 0 to 80°C (32 to 176°F) 0.5 to 3.4 V
C38-34 (THW) - C38-27 (ETHW) B - BR Engine coolant temperature sensor Idling, engine coolant temperature at 80°C (176°F) 0.2 to 1.0 V
G49-22 (STA) - C41-1 (E1) GR - W-B Starter signal Cranking 6.0 V or higher
C38-6 (#1D+) - C38-7 (#1D-) W - B No. 1 Injector assembly signal Idling

Pulse generation

(See waveform 2)

C38-1 (#2D+) - C38-2 (#2D-) R - W No. 2 Injector assembly signal
C39-7 (#3D+) - C39-6 (#3D-) G - R No. 3 Injector assembly signal
C38-5 (#4D+) - C38-4 (#4D-) Y - L No. 4 Injector assembly signal
C41-17 (VCG) - C41-18 (G2-) B - W Power source of camshaft position sensor (specific voltage) Engine switch on (IG) 4.5 to 5.5 V
C41-27 (G2+) - C41-18 (G2-) R - W Camshaft position sensor signal Idling

Pulse generation

(See waveform 3)

C41-20 (VCNE) - C41-19 (NE-) W - R Power source of crankshaft position sensor (specific voltage) Engine switch on (IG) 4.5 to 5.5 V
C41-28 (NE+) - C41-19 (NE-) Y - R Crankshaft position sensor signal Idling

Pulse generation

(See waveform 4)

G50-13 (STP) - C41-1 (E1) L - W-B Stop light switch assembly signal Engine switch on (IG) , brake pedal depressed 7.5 to 14 V
Engine switch on (IG) , brake pedal released 0 to 1.5 V
G50-12 (ST1-) - C41-1 (E1) GR - W-B

Stop light switch assembly signal

(opposite to STP)

Engine switch on (IG) , brake pedal depressed 0 to 1.5 V
Engine switch on (IG) , brake pedal released 7.5 to 14 V
G49-25 (TC) - C41-1 (E1) R - W-B Terminal TC of DLC3 Engine switch on (IG) 11 to 14 V
G49-10 (SPD) - C41-1 (E1) V - W-B Speed signal from combination meter assembly Engine switch on (IG) , slowly wheel rotated

Pulse generation

(See waveform 5)

C38-28 (VCPM) - C38-19 (EPIM) R - BR Power source of manifold absolute pressure sensor (specific voltage) Engine switch on (IG) 4.5 to 5.5 V
C38-18 (PIM) - C38-19 (EPIM) L - BR Manifold absolute pressure sensor Negative pressure of 40 kPa (300 mmHg, 11.8 in.Hg) applied 0.1 to 0.7 V
Same as atmospheric pressure 0.8 to 1.5 V
Positive pressure of 170 kPa (1275 mmHg, 50.2 in.Hg) applied 1.6 to 2.3 V
G49-16 (TACH) - C41-1 (E1) V - W-B Engine speed Idling

Pulse generation

(See waveform 6)

C40-28 (VCM) - C40-19 (E2M) G - R Power source of fuel pressure sensor (for PCR1) Engine switch on (IG) 4.5 to 5.5 V
C40-18 (PCR1) - C40-19 (E2M) W - R Fuel pressure sensor signal (main) Idling 1.8 to 2.1 V
C41-33 (VCS) - C41-25 (E2S) B - P Power source of fuel pressure sensor (for PCR2) Engine switch on (IG) 4.5 to 5.5 V
C41-26 (PCR2) - C41-25 (E2S) R - P Fuel pressure sensor signal (sub) Idling 1.2 to 1.5 V
C39-3 (PCV+) - C39-4 (PCV-) G - R Pre-stroke control valve operation signal Idling

Pulse generation

(See waveform 7)

C39-2 (PRV+) - C39-1 (PRV-) B - Y Pressure discharge valve signal Engine switch turned off after idling Pulse generation
C40-1 (VNM+) - C41-1 (E1) G - W-B DC motor signal (turbocharger nozzle vane control actuator) Idling Pulse generation
C40-2 (VNM-) - C41-1 (E1) W - W-B DC motor signal (turbocharger nozzle vane control actuator) Idling Pulse generation
C40-30 (VNVC) - C40-22 (VNE2) R - W Power source of nozzle vane position sensor (turbocharger nozzle vane control actuator) Engine switch on (IG) 4.5 to 5.5 V
C40-23 (VNA) - C40-22 (VNE2) P - W Nozzle vane position sensor signal (turbocharger nozzle vane control actuator) Engine switch on (IG) 2.3 to 2.7 V
C40-29 (VCVL) - C40-20 (EVLU) Y - L Power source of throttle position sensor Engine switch on (IG) 4.5 to 5.5 V
C40-21 (VLU) - C40-20 (EVLU) W- L Throttle position sensor signal

Engine switch on (IG) , throttle valve

fully opened

3.6 to 4.2 V

Engine switch on (IG) , throttle valve

fully closed

0.4 to 1.0 V
C41-6 (M+) - C41-3 (ME01) G - W-B Diesel throttle duty signal Engine warmed up, racing engine Pulse generation
C41-5 (M-) - C41-3 (ME01) R - W-B Diesel throttle duty signal Engine warmed up, racing engine Pulse generation
C40-31 (VCEG) - C40-24 (EEGL) R - W Power source of EGR valve position sensor Engine switch on (IG) 4.5 to 5.5 V
C40-25 (EGLS) - C40-24 (EEGL) G - W EGR valve position sensor Engine switch on (IG) 0.6 to 1.4 V
C40-6 (EGM+) - C41-1 (E1) B - W-B EGR valve duty signal Engine warmed up, idling Pulse generation
C40-7 (EGM-) - C41-1 (E1) W - W-B EGR valve duty signal Engine warmed up, idling Pulse generation
C38-16 (ECBV) - C41-1 (E1) L - W-B Vacuum switching valve assembly (for EGR bypass valve) Vacuum switching valve assembly (for EGR bypass valve) on 0 to 1.5 V
Vacuum switching valve assembly (for EGR bypass valve) off 11 to 14 V
G49-23 (NEO) - C41-1 (E1) G - W-B Crankshaft position sensor signal sent to certification ECU (smart key ECU assembly) Engine warmed up, idling

Pulse generation

(See waveform 8)

G50-15 (AC1) - C40-3 (E01) GR - W-B A/C signal A/C switch on 0 to 1.5 V
A/C switch off 11 to 14 V
G50-14 (ACT) - C40-3 (E01) LG - W-B A/C signal Engine switch on (IG) 11 to 14 V
A/C cut control on 0 to 3 V
G49-28 (CANL) - C41-1 (E1) W - W-B CAN communication line Engine switch on (IG)

Pulse generation

(See waveform 9)

G49-17 (CANH) - C41-1 (E1) B - W-B CAN communication line Engine switch on (IG)

Pulse generation

(See waveform 10)

C41-7 (LIN) - C41-1 (E1) P - W-B LIN communication line Engine switch on (IG)

Pulse generation

(See waveform 11)

C40-3 (E01) - Body ground W-B - Body ground Earth (ground) circuit of ECM Always Below 1 Ω
C41-4 (E02) - Body ground W-B - Body ground Earth (ground) circuit of ECM Always Below 1 Ω
C41-1 (E1) - Body ground W-B - Body ground Earth (ground) circuit of ECM Always Below 1 Ω
C41-3 (ME01) - Body ground W-B - Body ground Earth (ground) circuit of ECM Always Below 1 Ω
G50-8 (EC) - Body ground BR - Body ground Earth (ground) circuit of ECM Always Below 1 Ω
C38-3 (E1D1) - Body ground W-B - Body ground Earth (ground) circuit of ECM Always Below 1 Ω
C39-5 (E1D2) - Body ground W-B - Body ground Earth (ground) circuit of ECM Always Below 1 Ω
C41-2 (E04) - Body ground W-B - Body ground Earth (ground) circuit of ECM Always Below 1 Ω

  1. WAVEFORM 1

    B003MB4E04
    *a 1 V/DIV.
    *b 100 μsec./DIV.
    Mass Air Flow Meter Sub-assembly Signal
    ECM Terminal Name Between VG and EVG
    Tester Range 1 V/DIV., 100 μsec./DIV.
    Condition Engine switch on (IG)
  2. WAVEFORM 2

    B003QPBE01
    *a 10 V/DIV.
    *b 1 msec./DIV.
    No. 1 (to No. 4) Injector Assembly Signal
    ECM Terminal Name

    Between #1D+ and #1D-

    Between #2D+ and #2D-

    Between #3D+ and #3D-

    Between #4D+ and #4D-

    Tester Range 10 V/DIV., 1 msec./DIV.
    Condition Idling with warm engine

    Tech Tips

    The waveform varies depending on the injector injection.

  3. WAVEFORM 3

    B003P07E01
    *a 5 V/DIV.
    *b 20 msec./DIV.
    Camshaft Position Sensor Signal
    ECM Terminal Name Between G2+ and G2-
    Tester Range 5 V/DIV., 20 msec./DIV.
    Condition Idling with warm engine

    Tech Tips

    The waveform varies depending on the engine speed.

  4. WAVEFORM 4

    B003RF3E01
    *a 2 V/DIV.
    *b 10 msec./DIV.
    Crankshaft Position Sensor Signal
    ECM Terminal Name Between NE+ and NE-
    Tester Range 2 V/DIV., 10 msec./DIV.
    Condition Idling with warm engine

    Tech Tips

    The waveform becomes shorter as the engine speed.

  5. WAVEFORM 5

    B003RXNE02
    *a 5 V/DIV.
    *b 10 msec./DIV.
    Vehicle Speed Signal
    ECM Terminal Name Between SPD and E1
    Tester Range 5 V/DIV., 10 msec./DIV.
    Condition Driving at vehicle speed of 40 km/h (25 mph)

    Tech Tips

    The wavelength becomes shorter as the vehicle speed increases.

  6. WAVEFORM 6

    B003OPZE05
    *a 5 V/DIV.
    *b 10 msec./DIV.
    Engine Speed Signal
    ECM Terminal Name Between TACH and E1
    Tester Range 5 V/DIV., 10 msec./DIV.
    Condition Idling with warm engine

    Tech Tips

    The wavelength becomes shorter as the engine speed increases.

  7. WAVEFORM 7

    B003Q3BE01
    *1 10 V/DIV.
    *2 20 msec./DIV.
    Pre-stroke Control Valve Signal
    ECM Terminal Name Between PCV+ and PCV-
    Tester Range 10 V/DIV., 20 msec./DIV.
    Condition Idling with warm engine

    Tech Tips

    The waveform varies depending on pre-stroke control valve operation.

  8. WAVEFORM 8

    B003OMHE13
    *a 1 V/DIV.
    *b 2 msec./DIV.
    Engine Speed Signal
    ECM Terminal Name Between NEO and E1
    Tester Range 1 V/DIV., 2 msec./DIV.
    Condition Idling with warm engine
  9. WAVEFORM 9

    B003S7DE01
    *a 1 V/DIV.
    *b 10 msec./DIV.
    CAN Communication Signal
    ECM Terminal Name Between CANL and E1
    Tester Range 1 V/DIV., 10 msec./DIV.
    Condition Engine stopped, engine switch on (IG)

    Tech Tips

    The waveform varies depending on the CAN communication signal.

  10. WAVEFORM 10

    B003SEDE01
    *a 1 V/DIV.
    *b 10 msec./DIV.
    CAN Communication Signal
    ECM Terminal Name Between CANH and E1
    Tester Range 1 V/DIV., 10 msec./DIV.
    Condition Engine stopped, engine switch on (IG)

    Tech Tips

    The waveform varies depending on the CAN communication signal.

  11. WAVEFORM 11

    B003JWGE01
    *a 2 V/DIV.
    *b 10 msec./DIV.
    LIN Communication Signal
    ECM Terminal Name Between LIN and E1
    Tester Range 2 V/DIV., 10 msec./DIV.
    Condition Engine stopped, engine switch on (IG)

    Tech Tips

    The waveform varies depending on the LIN communication signal.