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Terminals Of ECM

Fig 1: Identifying ECM Terminals
GTY167120Courtesy 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 Conditions" 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
A21-20 (BATT) - C19-104 (E1) Y - W Battery (for measuring battery voltage and for ECM memory) Always 11 to 14 V
A21-2 (+B) - C19-104 (E1) B - W Power source of ECM Ignition switch ON 11 to 14 V
A21-1 (+B2) - C19-104 (E1) B - W Power source of ECM Ignition switch ON 11 to 14 V
A21-3 (+BM) - C19-104 (E1) GR - W Power source of throttle actuator Always 11 to 14 V
C19-85 (IGT1) - C19-104 (E1) W - W Ignition coil
(ignition signal)
Idling Pulse generation
(see waveform 1)
C19-84 (IGT2) - C19-104 (E1) L - W
C19-83 (IGT3) - C19-104 (E1) G - W
C19-82 (IGT4) - C19-104 (E1) B - W
C19-81 (IGF1) - C19-104 (E1) Y - W Ignition coil
(ignition confirmation signal)
Ignition switch ON 4.5 to 5.5 V
Idling Pulse generation
(see waveform 1)
C19-122 (NE+) - C19-121 (NE-) R - G Crankshaft position sensor Idling Pulse generation
(see waveform 2)
C19-99 (G2+) - C19-98 (G2-) P - W Camshaft position sensor (for intake camshaft) Idling Pulse generation
(see waveform 2)
C19-76 (EV1+) - C19-75 (EV1-) P - G Camshaft position sensor (for exhaust camshaft) Idling Pulse generation
(see waveform 2)
C19-108 (#10) - C19-45 (E01) R - BR Fuel injector Ignition switch ON 11 to 14 V
C19-107 (#20) - C19-45 (E01) Y - BR
C19-106 (#30) - C19-45 (E01) P - BR Idling Pulse generation
(see waveform 3)
C19-105 (#40) - C19-45 (E01) L - BR
C19-109 (HA1A) - C19-46 (E04) G - W-B Air fuel ratio sensor (sensor 1) heater Ignition switch ON 11 to 14 V
Idling Pulse generation
(see waveform 4)
C19-112 (A1A+) - C19-113 (A1A-) Y - BR Air fuel ratio sensor (sensor 1) Idling Below 3.3 V* 1
C19-47 (HT1B) - C19-86 (E03) R - W-B Heated oxygen sensor (sensor 2) heater Ignition switch ON 11 to 14 V
Idling Below 3.0 V
C19-64 (OX1B) - C19-87 (EX1B) W - P Heated oxygen sensor (sensor 2) Engine speed maintained at 2,500 rpm for 2 minutes after warming up sensor Pulse generation
(see waveform 5)
C19-110 (KNK1) - C19-111 (EKNK) R - G Knock sensor Engine speed maintained at 4,000 after warming up engine Pulse generation
(see waveform 6)
A21-8 (SPD) - C19-104 (E1) V - W Speed signal from combination meter Driving at 20 km/h (12 mph) Pulse generation
(see waveform 7)
C19-97 (THW) - C19-96 (ETHW) L - P Engine coolant temperature sensor Idling, Engine coolant temperature 80°C (176°F) 0.2 to 1.0 V
C19-65 (THA) - C19-88 (ETHA) Y - L Intake air temperature sensor (built into mass air flow meter Idling, Intake air temperature 20°C (68°F) 0.5 to 3.4 V
C19-118 (VG) - C19-116 (E2G) P - G Mass air flow meter Idling, transmission gear neutral, A/C switch OFF 0.5 to 3.0 V
A21-24 (W) - C19-104 (E1) B - W MIL Ignition switch ON (MIL goes ON) Below 3.0 V
Idling 11 to 14 V
A21-48 (STA) - C19-104 (E1) BR - W Starter signal Ignition switch ON Below 1.5 V
Cranking 5.5 V or more
C19-52 (STAR) - C19-104 (E1) B - W Starter relay control Ignition switch ON Below 1.5 V
Cranking 5.5 V or more
A21-13 (ACCR) - C19-104 (E1) G - W ACC (cut) relay control signal Ignition switch ON 11 to 14 V
Cranking Below 1.5 V
A21-14 (STSW) - C19-104 (E1) B - W Starter relay operation signal Ignition switch ON Below 1.5 V
Cranking 11 to 14 V
C19-115 (VTA1) - C19-91 (ETA) Y - B Throttle position sensor (for engine control) Ignition switch ON, Accelerator pedal released 0.5 to 1.1 V
Ignition switch ON, Accelerator pedal depressed 3.2 to 4.8 V
C19-114 (VTA2) - C19-91 (ETA) P - B 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 4.6 to 5.0 V
C19-67 (VCTA) - C19-91 (ETA) W - B Power source of sensor (specific voltage) Ignition switch ON 4.5 to 5.5 V
A21-57 (VCPA) - A21-59 (EPA) B - G Power source of accelerator pedal position sensor (for VPA) Ignition switch ON 4.5 to 5.5 V
A21-55 (VPA) - A21-59 (EPA) R - G Accelerator pedal position sensor (for engine control) Ignition switch ON, Accelerator pedal released 0.5 to 1.1 V
Ignition switch ON, Accelerator pedal fully depressed 2.5 to 4.5 V
A21-56 (VPA2) - A21-60 (EPA2) L - BR Accelerator pedal position sensor (for sensor malfunctioning detection) Ignition switch ON, Accelerator pedal released 1.2 to 2.0 V
Ignition switch ON, Accelerator pedal fully depressed 3.4 to 5.5 V
A21-58 (VCP2) - A21-60 (EPA2) W - BR Power source of accelerator pedal position sensor (for VPA2) Ignition switch ON 4.5 to 5.5 V
C19-42 (M+) - C19-43 (ME01) G - BR Throttle actuator Idling with warm engine Pulse generation
(see waveform 8)
C19-41 (M-) - C19-43 (ME01) R - BR Throttle actuator Idling with warm engine Pulse generation
(see waveform 9)
A21-36 (STP) - C19-104 (E1) G - W Stop light switch Brake pedal depressed 11 to 14 V
Brake pedal released Below 1.5 V
A21-35 (ST1-) - C19-104 (E1) Y - W Stop light switch Ignition switch ON, Brake pedal depressed Below 1.5 V
Ignition switch ON, Brake pedal released 11 to 14 V
C19-49 (PRG) - C19-104 (E1) L - W Purge VSV Ignition switch ON 11 to 14 V
Idling, under purge control Pulse generation
(see waveform 10)
A21-7 (FC) - C19-104 (E1) V - W Fuel pump control Ignition switch ON 11 to 14 V
Idling Below 1.5 V
A21-15 (TACH) - C19-104 (E1) LG - W Engine speed Idling Pulse generation
(see waveform 11)
A21-27 (TC) - C19-104 (E1) P - W Terminal TC of DLC3 Ignition switch ON 11 to 14 V
C19-100 (OC1+) - C19-123 (OC1-) Y - B Camshaft timing oil control valve (OCV) (for intake camshaft) Idling Pulse generation
(see waveform 12)
A21-41 (CANH) - C19-104 (E1) L - W CAN communication line Ignition switch ON Pulse generation
(see waveform 13)
A21-49 (CANL) - C19-104 (E1) W - W CAN communication line Ignition switch ON Pulse generation
(see waveform 14)
A21-21 (FAN) - C19-104 (E1) R - W NO. 1 FAN relay Ignition switch ON 11 to 14 V
Idling with A/C ON
or
High engine coolant temperature
Below 1.5 V
A21-22 (FAN2) - C19-104 (E1) LG - W NO. 2 FAN relay Idling with high engine coolant temperature Below 1.5 V
A21-28 (IGSW) - C19-104 (E1) R - W Ignition switch Ignition switch ON 11 to 14 V
A21-44 (MREL) - C19-104 (E1) GR - W EFI relay Ignition switch ON 11 to 14 V
C19-60 (OE1+) - C19-61 (OE1-) L - W Camshaft timing oil control valve (OCV) (for exhaust camshaft) Ignition switch ON Pulse generation
(see waveform 15)
C19-70 (VCV1) - C19-104 (E1) R - W Power source of camshaft position sensor (for intake camshaft) Ignition switch ON 4.5 to 5.5 V
C19-117 (VC) - C19-104 (E1) L - W Power source of camshaft position sensor (for exhaust camshaft) Ignition switch ON 4.5 to 5.5 V
A21-31 (ELS) - C19-104 (E1) G - W Electric load Tail light switch ON 7.5 to 14 V
Tail light switch ON Below 1.5 V
A21-33 (ELS3) - C19-104 (E1) V - W Electric load Defogger switch ON 7.5 to 14 V
Defogger switch ON Below 1.5 V
A21-42 (VPMP) - C19-104 (E1) P - W Vent valve (built into canister pump module) Ignition switch ON 11 to 14 V
A21-34 (MPMP) - C19-104 (E1) V - W Leak detection pump (built into canister pump module) Leak detection pump OFF Below 3 V
Leak detection pump ON 11 to 14 V
C19-69 (VCPP) - C19-92 (EPPM) V - B Power source for canister pressure sensor (specific voltage) Ignition switch ON 4.5 to 5.5 V
C19-68 (PPMP) - C19-92 (EPPM) L - B Canister pressure sensor (built into canister pump module) Ignition switch ON 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: Waveform 1 Graph
    GTY166084Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    IGNITER IGT SIGNAL (FROM ECM TO IGNITER)

    ECM Terminal Name Between IGT (1 to 4) and E1
    Between IGF1 and E1
    Tester Range 2 v/DIV, 20 ms/DIV
    Condition Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  2. WAVEFORM 2 
    Fig 3: Waveform 2 Graph
    GTY162389Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CRANKSHAFT POSITION SENSOR AND CAMSHAFT POSITION SENSOR

    ECM Terminal Name Between NE+ and NE-
    Between G2+ and G2-
    Between EV1+ and EV1-
    Tester Range 5 v/DIV, 20 ms/DIV
    Condition Idle after engine warmed-up

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  3. WAVEFORM 3 
    Fig 4: Waveform 3 Graph
    GTY164409Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    NO. 1 (TO NO. 4) INJECTOR 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 rpm increases.

  4. WAVEFORM 4 
    Fig 5: Waveform 4 Graph
    GTY165837Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    AIR FUEL RATIO SENSOR (SENSOR 1) HEATER

    ECM Terminal Name Between HA1A and E04
    Tester Range 5 v/DIV, 10 ms/DIV
    Condition Idling with warm engine

    HINT: 

    The wavelength varies in accordance with the engine operating condition.

  5. WAVEFORM 5 
    Fig 6: Waveform 5 Graph
    GTY166128Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    HEATED OXYGEN SENSOR (SENSOR 2)

    ECM Terminal Name Between OX1B and EX1B
    Tester Range 0.2 v/DIV, 200 ms/DIV
    Condition Maintain engine speed at 2,500 rpm for 2 minutes after warming up sensor

    HINT: 

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

  6. WAVEFORM 6 
    Fig 7: Waveform 6 Graph
    GTY162062Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    KNOCK SENSOR

    ECM Terminal Name Between KNK1 and EKNK
    Tester Range 500 mv/DIV, 1 ms/DIV
    Condition Maintain engine RPM at 4,000 rpm after engine warmed-up

    HINT: 

    • The wavelength becomes shorter as the engine rpm increases.
    • The waveforms and amplitudes displayed differ slightly depending on the vehicle condition.
  7. WAVEFORM 7 
    Fig 8: Waveform 7 Graph
    GTY164112Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    VEHICLE SPEED SIGNAL

    ECM Terminal Name Between SPD and E1
    Tester Range 5 v/DIV, 20 ms/DIV
    Condition Rotate driving wheel slowly

    HINT: 

    The wavelength becomes shorter as the vehicle speed increases.

  8. WAVEFORM 8 
    Fig 9: Waveform 8 Graph
    GTY162924Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    THROTTLE ACTUATOR POSITIVE TERMINAL

    ECM Terminal Name Between M+ and ME01
    Tester Range 5 v/DIV, 1 ms/DIV
    Condition Idle after engine warmed-up

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

  9. WAVEFORM 9 
    Fig 10: Waveform 9 Graph
    GTY163188Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    THROTTLE ACTUATOR NEGATIVE TERMINAL

    ECM Terminal Name Between M- and ME01
    Tester Range 5 v/DIV, 1 ms/DIV
    Condition Idle after engine warmed-up

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

  10. WAVEFORM 10 
    Fig 11: Waveform 10 Graph
    GTY162195Courtesy 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: Waveform 11 Graph
    GTY166392Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    ENGINE SPEED SIGNAL

    ECM Terminal Name Between TACH and E1
    Tester Range 5 v/DIV, 10 ms/DIV
    Condition Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  12. WAVEFORM 12 
    Fig 13: Waveform 12 Graph
    GTY166653Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT TIMING OIL CONTROL VALVE (OCV) (FOR INTAKE CAMSHAFT)

    ECM Terminal Name Between OC1+ and OC1-
    Tester Range 5 v/DIV, 1 ms/DIV
    Condition Idling
  13. WAVEFORM 13 
    Fig 14: Waveform 13 Graph
    GTY162544Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAN COMMUNICATION SIGNAL (REFERENCE)

    ECM Terminal Name Between CANH and E1
    Tester Range 1 v/DIV, 10 μs/DIV
    Condition Engine stop and ignition switch ON

    HINT: 

    The waveform varies depending on the CAN communication signal.

  14. WAVEFORM 14 
    Fig 15: Waveform 14 Graph
    GTY162036Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAN COMMUNICATION SIGNAL (REFERENCE)

    ECM Terminal Name Between CANL and E1
    Tester Range 1 v/DIV, 10 μs/DIV
    Condition Engine stop and ignition switch ON

    HINT: 

    The waveform varies depending on the CAN communication signal.

  15. WAVEFORM 15 
    Fig 16: Waveform 15 Graph
    GTY166627Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT TIMING OIL CONTROL VALVE (OCV) (FOR EXHAUST CAMSHAFT)

    ECM Terminal Name Between OE1+ and OE1-
    Tester Range 5 v/DIV, 1 ms/DIV
    Condition Idling