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Terminals Of ECM

Fig 1: ECM Connector Terminal Identification - SFI
GTY217326Courtesy 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, and 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
A57-20 (BATT) - D28-104 (E1) R - BR Auxiliary battery (for measuring auxiliary battery voltage and for ECM memory) Always 11 to 16 V
A57-2 (+B) - D28-104 (E1) B - BR Power source of ECM Power switch on (IG) 11 to 14 V
A57-1 (+B2) - D28-104 (E1) B - BR Power source of ECM Power switch on (IG) 11 to 14 V
A57-3 (+BM) - D28-104 (E1) GR - BR Power source of throttle actuator Always 11 to 16 V
D28-108 (IGT1) - D28-104 (E1) GR - BR Ignition coil assembly
(ignition signal)
Idling Pulse generation
(see waveform 1)
D28-107 (IGT2) - D28-104 (E1) W - BR
D28-106 (IGT3) - D28-104 (E1) G - BR
D28-105 (IGT4) - D28-104 (E1) Y - BR
D28-23 (IGF) - D28-104 (E1) L - BR Ignition coil assembly
(ignition confirmation signal)
Power switch on (IG) 4.5 to 5.5 V
Idling Pulse generation
(see waveform 1)
D28-74 (NE+) - D28-120 (NE-) B - W Crankshaft position sensor Idling with warm engine Pulse generation
(see waveform 2)
D28-76 (G2+) - D28-122 (G2-) B - W Camshaft position sensor Idling with warm engine Pulse generation
(see waveform 3)
D28-85 (#10) - D28-109 (E01) Y - BR Fuel injector assembly Idling Pulse generation
(see waveform 4)
D28-84 (#20) - D28-109 (E01) B - BR
D28-83 (#30) - D28-109 (E01) L - BR
D28-82 (#40) - D28-109 (E01) R - BR
D28-85 (#10) - D28-109 (E01) Y - BR Fuel injector assembly Power switch on (IG) 11 to 14 V
D28-84 (#20) - D28-109 (E01) B - BR
D28-83 (#30) - D28-109 (E01) L - BR
D28-82 (#40) - D28-109 (E01) R - BR
D28-18 (HA1A) - D28-46 (E04) Y - BR Air fuel ratio sensor (sensor 1) heater Power switch on (IG) 11 to 14 V
Idling Pulse generation
(see waveform 5)
D28-103 (A1A+) - D28-104 (E1) Y - BR Air fuel ratio sensor (sensor 1) Idling 3.3 V* 1
D28-126 (A1A-) - D28-104 (E1) BR - BR Air fuel ratio sensor (sensor 1) Idling 3.0 V* 1
D28-41 (HT1B) - D28-86 (E03) BR - BR Heated oxygen sensor (sensor 2) heater Power switch on (IG) 11 to 14 V
Idling Below 3.0 V
D28-125 (OX1B) - D28-102 (O1B-) L - P Heated oxygen sensor (sensor 2) Engine speed maintained at 2500 RPM for 2 minutes after warming up engine Pulse generation
(see waveform 6)
D28-87 (KNK1) - D28-110 (EKNK) B - W Knock control sensor Engine speed maintained at 2500 RPM after warming up engine Pulse generation
(see waveform 7)
D28-64 (THW) - D28-65 (ETHW) P - BR Engine coolant temperature sensor Idling, Engine coolant temperature 80°C (176°F) 0.2 to 1.0 V
D28-116 (THA) - D28-93 (ETHA) P - BR Intake air temperature sensor (built into mass air flow meter sub-assembly) Idling, Intake air temperature 20°C (68°F) 0.5 to 3.4 V
D28-94 (VG) - D28-117 (E2G) B - W Mass air flow meter sub-assembly Idling, shift lever in N, A/C switch OFF 0.5 to 3.0 V
A57-36 (W) - D28-104 (E1) LG - BR MIL Power switch on (IG) (MIL goes on) Below 3.0 V
Power switch on (READY) 11 to 14 V
D28-90 (VTA1) - D28-111 (ETA) Y - G Throttle position sensor (for engine control) Power switch on (IG),
Accelerator pedal fully released
0.5 to 1.1 V
D28-89 (VTA2) - D28-111 (ETA) B - G Throttle position sensor (for sensor malfunction detection) Power switch on (IG), Accelerator pedal fully released 2.1 to 3.1 V
D28-88 (VCTA) - D28-111 (ETA) R - G Power source of sensor (specific voltage) Power switch on (IG) 4.5 to 5.5 V
D28-21 (M+) - D28-19 (ME01) L - BR Throttle actuator Idling with warm engine Pulse generation
(see waveform 8)
D28-20 (M-) - D28-19 (ME01) P - BR Throttle actuator Idling with warm engine Pulse generation
(see waveform 9)
D28-28 (PRG) - D28-104 (E1) V - BR Purge VSV Power switch on (IG) 11 to 14 V
Idling, under purge control Pulse generation
(see waveform 10)
A57-8 (FC) - D28-104 (E1) R - BR Fuel pump control Power switch on (IG) 11 to 14 V
Idling Below 1.5 V
A57-7 (TC) - D28-104 (E1) P - BR Terminal TC of DLC3 Power switch on (IG) 11 to 14 V
D28-36 (OC1+) - D28-59 (OC1-) Y - G Camshaft timing oil control valve assembly Idling Pulse generation
(see waveform 11)
A57-13 (CANH) - D28-104 (E1) P - BR CAN communication line Engine stopped and power switch on (IG) Pulse generation
(see waveform 12)
A57-5 (CANL) - D28-104 (E1) V - BR CAN communication line Engine stopped and power switch on (IG) Pulse generation
(see waveform 13)
A57-12 (CANP) - D28-104 (E1) B - BR CAN communication line Engine stopped and power switch on (IG) Pulse generation
(see waveform 12)
A57-4 (CANN) - D28-104 (E1) W - BR CAN communication line Engine stopped and power switch on (IG) Pulse generation
(see waveform 13)
A57-28 (IGSW) - D28-104 (E1) W - BR Power switch Power switch on (IG) 11 to 14 V
A57-6 (MREL) - D28-104 (E1) G - BR EFI MAIN relay Power switch on (IG) 11 to 14 V
D28-99 (VCV1) - D28-104 (E1) R - BR Power source of camshaft position sensor Power switch on (IG) 4.5 to 5.5 V
A57-10 (WPO) - D28-104 (E1) L - BR Engine water pump assembly Idling with warm engine Pulse generation
(see waveform 14)
A57-11 (WPI) - D28-104 (E1) G - BR Engine water pump assembly Idling with warm engine Pulse generation
(see waveform 15)
D28-72 (VCPM) - D28-71 (EPIM) L - Y Manifold absolute pressure sensor Power switch on (IG) 4.75 to 5.25 V
D28-69 (PIM) - D28-71 (EPIM) B - Y Manifold absolute pressure sensor Power switch on (IG) 3.0 to 5.5 V
D28-45 (EGR1) - D28-104 (E1) R - BR EGR valve assembly EGR valve operating Pulse generation
(see waveform 16)
D28-44 (EGR2) - D28-104 (E1) V - BR EGR valve assembly EGR valve operating Pulse generation
(see waveform 16)
D28-43 (EGR3) - D28-104 (E1) Y - BR EGR valve assembly EGR valve operating Pulse generation
(see waveform 16)
D28-42 (EGR4) - D28-104 (E1) LG - BR EGR valve assembly EGR valve operating Pulse generation
(see waveform 16)
D28-48 (G2O) - D28-104 (E1) Y - BR Camshaft revolution signal Idling Pulse generation
(see waveform 17)
A57-22 (FANH) - D28-104 (E1) LG - BR Cooling fan relay Power switch on (IG), Cooling fan not operated 11 to 14 V
A57-21 (FANL) - D28-104 (E1) L - BR Cooling fan relay Power switch on (IG), Cooling fan not operated 11 to 14 V
A57-46 (PWMS) - D28-104 (E1) G - BR Power mode switch Power switch on (IG), Power mode switch off 11 to 14 V
Power switch on (IG), Power mode switch on 0 to 1.5 V
D28-104 (E1) - Body ground BR - Body ground Ground Always Below 1 Ω
D28-109 (E01) - Body ground BR - Body ground Ground Always Below 1 Ω
D28-81 (E02) - Body ground W-B - Body ground Ground Always Below 1 Ω
D28-86 (E03) - Body ground BR - Body ground Ground Always Below 1 Ω
D28-46 (E04) - Body ground BR - Body ground Ground Always Below 1 Ω
A57-32 (EC) - Body ground W-B - Body ground Ground Always Below 1 Ω
D28-22 (GE01) - D28-104 (E1) W-B - BR Shield earth (ground) circuit of throttle actuator Always Below 1 V
A57-42 (VPMP) - D28-104 (E1) B - BR Vent valve (built into canister pump module) Power switch on (IG) 11 to 14 V
A57-34 (MPMP) - D28-104 (E1) L - BR Leak detection pump (built into canister pump module) Leak detection pump OFF Below 3 V
Leak detection pump ON 9 to 14 V
D28-113 (VCPP) - D28-112 (EPPM) GR - LG Power source for canister pressure sensor (specific voltage) Power switch on (IG) 4.5 to 5.5 V
D28-114 (PPMP) - D28-112 (EPPM) W - LG Canister pressure sensor (built into canister pump module) Power switch on (IG) 3 to 3.6 V

HINT: 

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

  1. WAVEFORM 1 
    Fig 2: Identifying Waveform 1
    GTY332680Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    IGNITER IGT SIGNAL (FROM ECM TO IGNITER) AND IGNITER IGF SIGNAL (FROM IGNITER TO ECM)

    ECM Terminal Name CH1: Between IGT (1 to 4) and E1
    CH2: Between IGF and E1
    Tester Range 2 V/DIV., 20 ms./DIV.
    Condition Idling

    HINT: 

    The wavelength becomes shorter as the engine speed increases.

  2. WAVEFORM 2 
    Fig 3: Identifying Waveform 2
    GTY309810Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CRANKSHAFT POSITION SENSOR SIGNAL

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

    HINT: 

    The wavelength becomes shorter as the engine speed increases.

  3. WAVEFORM 3 
    Fig 4: Identifying Waveform 3
    GTY309342Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT POSITION SENSOR SIGNAL

    ECM Terminal Name Between G2+ and G2-
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling with warm engine

    HINT: 

    The wavelength becomes shorter as the engine speed increases.

  4. WAVEFORM 4 
    Fig 5: Identifying Waveform 4
    GTY290569Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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

    HINT: 

    The wavelength becomes shorter as the engine speed increases.

  5. WAVEFORM 5 
    Fig 6: Identifying Waveform 5
    GTY238005Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    AIR FUEL RATIO SENSOR (SENSOR 1) HEATER SIGNAL

    ECM Terminal Name Between HA1A and E04
    Tester Range 5 V/DIV., 10 ms./DIV.
    Condition Idling

    HINT: 

    The wavelength varies in accordance with the engine operating condition.

  6. WAVEFORM 6 
    Fig 7: Identifying Waveform 6
    GTY286446Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    HEATED OXYGEN SENSOR (SENSOR 2) SIGNAL

    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 warming up engine

    HINT: 

    In the Data List, the items O2S B1S2 show the values input to the ECM from the heated oxygen sensor.

  7. WAVEFORM 7 
    Fig 8: Identifying Waveform 7
    GTY238464Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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

    HINT: 

    • The wavelength becomes shorter as the engine speed increases.
    • The waveforms and amplitudes displayed differ slightly depending on the vehicle condition.
  8. WAVEFORM 8 
    Fig 9: Identifying Waveform 8
    GTY290954Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

  9. WAVEFORM 9 
    Fig 10: Identifying Waveform 9
    GTY292199Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

  10. WAVEFORM 10 
    Fig 11: Identifying Waveform 10
    GTY235665Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    PURGE VSV

    ECM Terminal Name Between PRG and E1
    Tester Range 10 V/DIV., 20 ms./DIV.
    Condition Idling, under purge control

    HINT: 

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

  11. WAVEFORM 11 
    Fig 12: Identifying Waveform 11
    GTY219442Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY SIGNAL

    ECM Terminal Name Between OC1+ and OC1-
    Tester Range 5 V/DIV., 1 ms./DIV.
    Condition Idling
  12. WAVEFORM 12 
    Fig 13: Identifying Waveform 12
    GTY222725Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAN COMMUNICATION SIGNAL (REFERENCE)

    ECM Terminal Name Between CANH and E1, CANP and E1
    Tester Range 1 V/DIV., 10 μsec./DIV.
    Condition Engine stopped and power switch on (IG)

    HINT: 

    The waveform varies depending on the CAN communication signal.

  13. WAVEFORM 13 
    Fig 14: Identifying Waveform 13
    GTY229520Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAN COMMUNICATION SIGNAL (REFERENCE)

    ECM Terminal Name Between CANL and E1, CANN and E1
    Tester Range 1 V/DIV., 10 μsec./DIV.
    Condition Engine stopped and power switch on (IG)

    HINT: 

    The waveform varies depending on the CAN communication signal.

  14. WAVEFORM 14 
    Fig 15: Identifying Waveform 14
    GTY229753Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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

    HINT: 

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

  15. WAVEFORM 15 
    Fig 16: Identifying Waveform 15
    GTY229753Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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

    HINT: 

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

  16. WAVEFORM 16 
    Fig 17: Identifying Waveform 16
    GTY224368Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    EGR VALVE ASSEMBLY SIGNAL

    ECM Terminal Name Between EGR1 and E1, EGR2 and E1, EGR3 and E1, EGR4 and E1
    Tester Range 20 V/DIV., 50 ms./DIV.
    Condition EGR valve operating
  17. WAVEFORM 17 
    Fig 18: Identifying Waveform 17
    GTY229753Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT REVOLUTION SIGNAL FROM ECM TO POWER MANAGEMENT CONTROL ECU AND INVERTER WITH CONVERTER ASSEMBLY (MG ECU)

    ECM Terminal Name Between G2O and E1
    Tester Range 5 V/DIV., 20 ms./DIV.
    Condition Idling

    HINT: 

    The wavelength becomes shorter as the engine speed increases.