LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Scion >> 2010 >> tC Standard >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Control System (Diagnostics - Introduction) >> SFI System >> Terminals Of ECM >> Terminals Of ECM
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Terminals Of ECM

Fig 1: Identifying ECM Connector Terminals
GTY161890Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT: 

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 the terminals displayed in the "Specified Condition" column. The illustration above can be used as a reference to identify the ECM terminal locations.

Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
E4-3 (BATT) - E8-3 (E1) V - L Battery (for measuring battery voltage and for ECM memory) Always 11 to 14 V
E4-7 (+BM) - E8-3 (E1) BR - L Power source of throttle motor Always 11 to 14 V
E4-9 (IGSW) - E8-3 (E1) G - L Ignition switch Ignition switch ON 11 to 14 V
E4-1 (+B) - E8-3 (E1) GR - L Power source of ECM Ignition switch ON 11 to 14 V
E4-2 (+B2) - E8-3 (E1) O - L Power source of ECM Ignition switch ON 11 to 14 V
E8-13 (OC1+) - E8-12 (OC1-) Y - W Camshaft timing oil control valve (OCV) Idling Pulse generation (See waveform 8)
E4-8 (MREL) - E8-7 (E01) O - B EFI relay Ignition switch ON 11 to 14 V
E8-18 (VC) - E8-28 (E2) V - R Power source of sensor (specific voltage) Ignition switch ON 4.5 to 5.5 V
E7-28 (VG) - E7-30 (E2G) R - W Mass air flow meter Idling, shift lever position P or N, A/C switch OFF 0.5 to 3.0 V
E7-29 (THA) - E8-28 (E2) L - R Intake air temperature sensor Idling, intake air temp. 20°C (68°F) 0.5 to 3.4 V
E8-32 (THW) - E8-28 (E2) G - R Engine coolant temperature sensor Idling, engine coolant temp. 80°C (176°F) 0.2 to 1.0 V
E8-20 (VTA1) - E8-28 (E2) LG - R Throttle position sensor (for engine control) Ignition switch ON, accelerator pedal released 0.3 to 1.0 V
Ignition switch ON, accelerator pedal depressed 3.2 to 4.9 V
E8-19 (VTA2) - E8-28 (E2) BR - R Throttle position sensor (for sensor malfunction detection) Ignition switch ON, accelerator pedal released 2.1 to 3.1 V
Ignition switch ON, accelerator pedal depressed 4.5 to 5.5 V
E4-18 (VPA) - E4-20 (EPA) W - BR Accelerator pedal position sensor (for engine control) Ignition switch ON, accelerator pedal released 0.5 to 1.1 V
Ignition switch ON, accelerator pedal depressed 2.6 to 4.5 V
E4-19 (VPA2) - E4-21 (EPA2) V - R Accelerator pedal position sensor (for sensor malfunction detection) Ignition switch ON, accelerator pedal released 1.2 to 2.0 V
Ignition switch ON, accelerator pedal depressed 3.4 to 5.0 V
E4-26 (VCPA) - E4-20 (EPA) L - BR Power source of accelerator pedal position sensor (for VPA) Ignition switch ON 4.5 to 5.5 V
E4-27 (VCP2) - E4-21 (EPA2) P - R Power source of accelerator pedal position sensor (for VPA2) Ignition switch ON 4.5 to 5.5 V
E8-1 (HA1A) - E7-7 (E04) G - W-B A/F sensor heater Idling Below 3.0 V
Ignition switch ON 11 to 14 V
E8-21 (A1A+) - E8-3 (E1) O - L A/F sensor Ignition switch ON 3.0 to 3.6 V
E8-31 (A1A-) - E8-3 (E1) W - L A/F sensor Ignition switch ON 2.7 to 3.3 V
E8-2 (HT1B) - E7-4 (E03) L - BR Heated oxygen sensor heater Idling Below 3.0 V
Ignition switch ON 11 to 14 V
E8-25 (OX1B) - E8-28 (E2) B - R Heated oxygen sensor Engine speed maintained at 2500 rpm for 2 minutes after warming up Pulse generation (See waveform 6)
E7-6 (#1) - E8-7 (E01)
E7-5 (#2) - E8-7 (E01)
E7-2 (#3) - E8-7 (E01)
E7-1 (#4) - E8-7 (E01)		 L - B
R - B
Y - B
W - B		 Injector Ignition switch ON 11 to 14 V
Idling Pulse generation (See waveform 1)
E8-29 (KNK1) - E8-30 (EKNK) R - G Knock sensor Engine speed maintained at 4000 rpm after warming up engine Pulse generation (See waveform 7)
E8-26 (G2+) - E8-34 (NE-) P - G Camshaft position sensor Idling Pulse generation (See waveform 3)
E8-27 (NE+) - E8-34 (NE-) R - G Crankshaft position sensor Idling Pulse generation (See waveform 3)
E8-17 (IGT1) - E8-3 (E1)
E8-16 (IGT2) - E8-3 (E1)
E8-15 (IGT3) - E8-3 (E1)
E8-14 (IGT4) - E8-3 (E1)		 G - L
P - L
B - L
LG - L		 Ignition coil with igniter (ignition signal) Idling Pulse generation (See waveform 2)
E8-23 (IGF1) - E8-3 (E1) V - L Ignition coil with igniter (ignition confirmation signal) Ignition switch ON 4.5 to 5.5 V
Idling Pulse generation (See waveform 2)
E7-23 (PRG) - E8-3 (E1) R - L Purge VSV Ignition switch ON 11 to 14 V
Idling Pulse generation (See waveform 9)
E5-8 (SPD) - E8-3 (E1) V - L Speed signal from combination meter Ignition switch ON, rotate driving wheel slowly Pulse generation (See waveform 11)
E4-12 (STA) - E8-3 (E1) B - L Starter signal Shift lever position P or N, ignition switch START 11 to 14 V
E5-4 (STP) - E8-3 (E1) L - L Stop light switch Brake pedal is depressed 7.5 to 14 V
Brake pedal is released Below 1.5 V
E4-16 (ST1-) - E8-3 (E1) L - L Stop light switch (opposite to STP terminal) Ignition switch ON,
Brake pedal is depressed		 Below 1.5 V
Ignition switch ON,
Brake pedal is released		 7.5 to 14 V
E4-30 (NSW) - E8-3 (E1) Y - L Park/neutral position switch Ignition switch ON, shift lever position P or N 0 to 3.0 V
Ignition switch ON, shift lever position not P or N 11 to 14 V
E8-5 (M+) - E7-3 (ME01) B - W-B Throttle actuator Idling with warm engine Pulse generation (See waveform 4)
E8-4 (M-) - E7-3 (ME01) W - W-B Throttle actuator Idling with warm engine Pulse generation (See waveform 5)
E4-25 (FC) - E8-7 (E01) L - B Fuel pump control Ignition switch ON 11 to 14 V
E5-30 (W) - E8-3 (E1) G - L MIL Ignition switch ON Below 3.0 V
Idling 11 to 14 V
E4-15 (ELS1) - E8-3 (E1) B - L Electric load Light control switch OFF 0 to 1.5 V
Light control switch is in TAIL position 11 to 14 V
E5-3 (ELS3) - E8-3 (E1) O - L Electric load Rear defogger switch OFF (Rear defogger system is not operating) 0 to 1.5 V
Rear defogger switch ON (Rear defogger system is operating) 11 to 14 V
E5-17 (TC) - E8-3 (E1) R - L Terminal TC of DLC 3 Ignition switch ON 11 to 14 V
E5-1 (TACH) - E8-3 (E1) B - L Engine speed Idling Pulse generation (See waveform 10)
E7-32 (PSW) - E8-3 (E1) R - L P/S pressure switch Ignition switch ON 11 to 14 V
E4-5 (VPMP) - E8-7 (E01) G - B Vent valve (built into canister pump module) Ignition switch ON 11 to 14 V
E4-6 (MPMP) - E8-7 (E01) L - B Leak detection pump (built into canister pump module) Leak detection pump OFF Below 3 V
Leak detection pump ON 11 to 14 V
E4-31 (PPMP) - E8-28 (E2) LG - R Canister pressure sensor (built into canister pump module) Ignition switch ON 3 to 3.6 V
E4-14 (FANH) - E8-7 (E01) GR - B Fan No. 2, 3 relay Idling with high engine coolant temperature Below 1.5 V
E8-10 (ALT) - E8-3 (E1) Y - L Generator Ignition switch ON 11 to 14 V
E5-33 (CANH) - E8-3 (E1) B - L CAN communication line Ignition switch ON Pulse generation (See waveform 12)
E5-34 (CANL) - E8-3 (E1) W - L CAN communication line Ignition switch ON Pulse generation (See waveform 13)
  1. WAVEFORM 1 
    Fig 2: Identifying Waveform 1
    GTY161859Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    FUEL INJECTOR

    Item Content
    ECM Terminal Names Between #1 (to 4) and E01
    Tester Ranges 20 V/DIV., 20 msec./DIV.
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  2. WAVEFORM 2 
    Fig 3: Identifying Waveform 2
    GTY145150Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    (A) IGNITER IGT SIGNAL (FROM ECM TO IGNITER)

    Item Content
    ECM Terminal Names Between IGT (1 to 4) and E1
    Tester Ranges 2 V/DIV., 20 msec./DIV.
    Conditions Idling
    (B) IGNITER IGF SIGNAL (FROM IGNITER TO ECM)

    Item Content
    ECM Terminal Names Between IGF1 and E1
    Tester Ranges 2 V/DIV., 20 msec./DIV.
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  3. WAVEFORM 3 
    Fig 4: Identifying Waveform 3
    GTY161883Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    (A) CAMSHAFT POSITION SENSOR

    Item Content
    ECM Terminal Names Between G2+ and NE-
    Tester Ranges 5 V/DIV., 20 msec./DIV.
    Conditions Idling
    (B) CRANKSHAFT POSITION SENSOR

    Item Content
    ECM Terminal Names Between NE+ and NE-
    Tester Ranges 5 V/DIV., 20 msec./DIV.
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  4. WAVEFORM 4 
    Fig 5: Identifying Waveform 4
    GTY144504Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    THROTTLE ACTUATOR POSITIVE TERMINAL

    Item Content
    ECM Terminal Names Between M+ and ME01
    Tester Ranges 5 V/DIV., 1 msec./DIV.
    Conditions Idling with warm engine

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

  5. WAVEFORM 5 
    Fig 6: Identifying Waveform 5
    GTY145146Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    THROTTLE ACTUATOR NEGATIVE TERMINAL

    Item Content
    ECM Terminal Names Between M- and ME01
    Tester Ranges 5 V/DIV., 1 msec./DIV.
    Conditions Idling with warm engine

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

  6. WAVEFORM 6 
    Fig 7: Identifying Waveform 6
    GTY145094Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    HEATED OXYGEN SENSOR

    Item Content
    ECM Terminal Names Between OX1B and E2
    Tester Ranges 0.2 V/DIV., 200 msec./DIV.
    Conditions Engine speed maintained at 2500 rpm for 2 minutes after warming up

    HINT: 

    In the Data List, item O2S B1S2 shows the ECM input values from the heated oxygen sensor.

  7. WAVEFORM 7 
    Fig 8: Identifying Waveform 7
    GTY165446Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    KNOCK SENSOR

    Item Content
    ECM Terminal Names Between KNK1 and EKNK
    Tester Ranges 0.01 to 10 V/DIV., 0.01 to 10 msec./DIV.
    Conditions Engine speed maintained at 4000 rpm after warming up engine

    HINT: 

    • The wavelength becomes shorter as the engine rpm increases.
    • The waveforms and amplitudes displayed differ slightly depending on the vehicle.
  8. WAVEFORM 8 
    Fig 9: Identifying Waveform 8
    GTY145142Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT TIMING OIL CONTROL VALVE (OCV)

    Item Content
    ECM Terminal Names Between OC1+ and OC1-
    Tester Ranges 5 V/DIV., 1 msec./DIV.
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  9. WAVEFORM 9 
    Fig 10: Identifying Waveform 9
    GTY165839Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    PURGE VSV

    Item Content
    ECM Terminal Names Between PRG and E1
    Tester Ranges 5 V/DIV., 50 msec./DIV.
    Conditions Idling

    HINT: 

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

  10. WAVEFORM 10 
    Fig 11: Identifying Waveform 10
    GTY145140Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    ENGINE SPEED SIGNAL

    Item Content
    ECM Terminal Names Between TACH and E1
    Tester Ranges 5 V/DIV., 10 msec./DIV.
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  11. WAVEFORM 11 
    Fig 12: Identifying Waveform 11
    GTY163866Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    VEHICLE SPEED SIGNAL

    Item Content
    ECM Terminal Names Between SPD and E1
    Tester Ranges 5 V/DIV., 20 msec./DIV.
    Conditions Ignition switch ON, rotate driving wheel slowly

    HINT: 

    The wavelength becomes shorter as the vehicle speed increases.

  12. WAVEFORM 12 
    Fig 13: Identifying Waveform 12
    GTY125259Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAN COMMUNICATION SIGNAL:

    ECM Terminal Names Between CANH and E1
    Tester Ranges 1 V/DIV., 10 μsec./DIV.
    Conditions Ignition switch ON

    HINT: 

    The waveform varies depending on the CAN communication signal.

  13. WAVEFORM 13 
    Fig 14: Identifying Waveform 13
    GTY144118Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAN COMMUNICATION SIGNAL:

    ECM Terminal Names Between CANL and E1
    Tester Ranges 1 V/DIV., 10 μsec./DIV.
    Conditions Ignition switch ON

    HINT: 

    The waveform varies depending on the CAN communication signal.

scientia non olet · About LEMON Manuals