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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
(Refer to 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
(Refer to waveform 1)
C19-122 (NE+) - C19-121 (NE-) R - G Crankshaft position sensor Idle after engine warmed-up Pulse generation
(Refer to waveform 2)
C19-99 (G2+) - C19-98 (G2-) P - W Camshaft position sensor (for intake camshaft) Pulse generation
(Refer to waveform 3)
C19-76 (EV1+) - C19-75 (EV1-) P - G Camshaft position sensor (for exhaust camshaft) Pulse generation
(Refer to waveform 3)
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
(Refer to waveform 4)
C19-105 (#40) - C19-45 (E01) L - BR
C19-109 (HA1A) - C19-46 (E04) G - W-B Air fuel ratio sensor heater Ignition switch ON 11 to 14 V
Idling with warm engine Pulse generation
(Refer to waveform 5)
C19-112 (A1A+) - C19-104 (E1) Y - W Air fuel ratio sensor Ignition switch ON 3.3 V*
C19-113 (A1A-) - C19-104 (E1) BR - W Air fuel ratio sensor Ignition switch ON 2.9 V*
C19-47 (HT1B) - C19-86 (E03) R - W-B Heated oxygen sensor heater Ignition switch ON 11 to 14 V
Idling Below 3.0 V
C19-64 (OX1B) - C19-87 (EX1B) W - P Heated oxygen sensor Maintain engine speed at 2500 rpm for 2 minutes after warming up sensor Pulse generation
(Refer to waveform 6)
C19-110 (KNK1) - C19-111 (EKNK) R - G Knock sensor Maintain engine speed at 4000 rpm after engine warmed-up Pulse generation
(Refer to waveform 7)
A21-8 (SPD) - C19-104 (E1) V - W Speed signal from combination meter Driving at 20 km/h (12 mph) Pulse generation
(Refer to waveform 8)
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, Shift lever position 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, Shift lever position in P and N (for Automatic Transaxle) or Clutch pedal fully depressed (for Manual Transaxle) 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 2.6 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 4.7 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
(Refer to waveform 9)
C19-41 (M-) - C19-43 (ME01) R - BR Throttle actuator Idling with warm engine Pulse generation
(Refer to waveform 10)
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
(Refer to waveform 11)
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
(Refer to waveform 12)
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 (for intake camshaft) Idling Pulse generation
(Refer to waveform 13)
A21-41 (CANH) - C19-104 (E1) L - W CAN communication line Ignition switch ON Pulse generation
(Refer to waveform 14)
A21-49 (CANL) - C19-104 (E1) W - W CAN communication line Ignition switch ON Pulse generation
Refer to waveform 15)
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 (for exhaust camshaft) Idling Pulse generation
Refer to waveform 16)
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 3.0 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 3.0 to 3.6 V

HINT: 

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

  1. WAVEFORM 1 
    Fig 2: Identifying Waveform 1
    GTY313721Courtesy 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 speed increases.

  2. WAVEFORM 2 
    Fig 3: Identifying Waveform 2
    GTY296838Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CRANKSHAFT POSITION SENSOR

    ECM Terminal Name Between NE+ and NE-
    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: Identifying Waveform 3
    GTY295355Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT POSITION SENSOR

    ECM Terminal Name 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.

  4. WAVEFORM 4 
    Fig 5: Identifying Waveform 4
    GTY314001Courtesy 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.

  5. WAVEFORM 5 
    Fig 6: Identifying Waveform 5
    GTY310584Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    AIR FUEL RATIO SENSOR 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.

  6. WAVEFORM 6 
    Fig 7: Identifying Waveform 6
    GTY344493Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    HEATED OXYGEN SENSOR

    ECM Terminal Name Between OX1B and EX1B
    Tester Range 200 mV/DIV, 200 ms/DIV
    Condition Maintain engine speed at 2500 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.

  7. WAVEFORM 7 
    Fig 8: Identifying Waveform 7
    GTY314034Courtesy 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 speed at 4000 rpm after engine warmed-up

    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
    GTY313192Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    VEHICLE SPEED SIGNAL

    ECM Terminal Name Between SPD and E1
    Tester Range 5 V/DIV, 20 ms/DIV
    Condition Driving at 20 km/h (12 mph)

    HINT: 

    The wavelength becomes shorter as the vehicle speed increases.

  9. WAVEFORM 9 
    Fig 10: Identifying Waveform 9
    GTY344696Courtesy 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 Idling with warm engine

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

  10. WAVEFORM 10 
    Fig 11: Identifying Waveform 10
    GTY345555Courtesy 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 Idling with warm engine

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

  11. WAVEFORM 11 
    Fig 12: Identifying Waveform 11
    GTY310424Courtesy 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.

  12. WAVEFORM 12 
    Fig 13: Identifying Waveform 12
    GTY312258Courtesy 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.

  13. WAVEFORM 13 
    Fig 14: Identifying Waveform 13
    GTY312027Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT TIMING OIL CONTROL VALVE (FOR INTAKE CAMSHAFT)

    ECM Terminal Name Between OC1+ and OC1-
    Tester Range 5 V/DIV, 1 ms/DIV
    Condition Idling
  14. WAVEFORM 14 
    Fig 15: Identifying Waveform 14
    GTY313064Courtesy 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.

  15. WAVEFORM 15 
    Fig 16: Identifying waveform 15
    GTY311920Courtesy 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.

  16. WAVEFORM 16 
    Fig 17: Identifying Waveform 16
    GTY312032Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CAMSHAFT TIMING OIL CONTROL VALVE (FOR EXHAUST CAMSHAFT)

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