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Terminals Of ECM

  1. CHECK ECM 
    Fig 1: Identifying ECM Connector Terminal Identification
    GTY229457Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the voltage of the ECM connectors.

      HINT: 

      The standard voltage between each pair of ECM terminals is shown in the table below. The appropriate conditions for checking each pair of terminals are also indicated. The result of checks should be compared with the standard voltage for that pair of terminals, 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
      F51-24 (BATT) - B38-12 (E1) L - BR Battery (for measuring battery voltage and for ECM memory) Always 11 to 14 V
      B38-23 (+BM) - B38-12 (E1) P-L - BR Power source of throttle actuator Always 11 to 14 V
      F50-21 (IGSW) - B38-12 (E1) W - BR Ignition switch Ignition switch ON 11 to 14 V
      F51-22 (+B) - B38-12 (E1) W - BR Power source of ECM Ignition switch ON 11 to 14 V
      F51-23 (+B2) - B38-12 (E1) W - BR Power source of ECM Ignition switch ON 11 to 14 V
      B37-19 (OC1+) - B37-20 (OC1-) R-W - GR Camshaft timing oil control valve (for intake side of bank 1) Ignition switch ON Pulse generation (see waveform 1 in step  b)
      B36-19 (OC2+) - B36-20 (OC2-) B-R - L-R Camshaft timing oil control valve (for intake side of bank 2) Ignition switch ON Pulse generation
      (see waveform 1 in step  b)
      B37-21 (OE1+) - B37-22 (OE1-) G-B - B-R Camshaft timing oil control valve (for exhaust side of bank 1) Ignition switch ON Pulse generation
      (see waveform 1 in step  b)
      B36-21 (OE2+) - B36-22 (OE2-) W-G - L Camshaft timing oil control valve (for exhaust side of bank 2) Ignition switch ON Pulse generation
      (see waveform 1 in step  b)
      F51-9 (MREL) - B38-12 (E1) V - BR EFI MAIN relay Ignition switch ON 11 to 14 V
      B37-14 (VG) - B37-13 (E2G) L-W - B-W Mass air flow meter Idling, shift lever in P or N, A/C switch off 0.5 to 3.0 V
      B37-15 (THA) - B37-7 (ETHA) Y - G Intake air temperature sensor Idling, intake air temperature 20°C (68°F) 0.5 to 3.4 V
      B38-17 (THW) - B37-8 (ETHW) G - W-R Engine coolant temperature sensor Idling, engine coolant temperature 80°C (176°F) 0.2 to 1.0 V
      B38-13 (VCTA) - B38-14 (ETA) R - W Power source for throttle position sensor (fixed voltage) Ignition switch ON 4.5 to 5.5 V
      B38-15 (VTA1) - B38-14 (ETA) LG - W Throttle position sensor (for engine control) Ignition switch ON,
      throttle valve fully closed      		 0.5 to 1.1 V
      Ignition switch ON,
      throttle valve fully open      		 3.3 to 4.9 V
      B38-16 (VTA2) - B38-14 (ETA) G-W - W Throttle position sensor (for sensor malfunction detection) Ignition switch ON,
      throttle valve fully closed      		 2.1 to 3.1 V
      Ignition switch ON,
      throttle valve fully open      		 4.6 to 5.0 V
      F50-6 (VPA) - F50-3 (EPA) L - P 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
      F50-5 (VPA2) - F50-1 (EPA2) GR - W 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 fully depressed      		 3.4 to 5.0 V
      F50-4 (VCPA) - F50-3 (EPA) LG - P Power source of accelerator pedal position sensor (for VPA) Ignition switch ON 4.5 to 5.5 V
      F50-2 (VCP2) - F50-1 (EPA2) R - W Power source of accelerator pedal position sensor (for VPA2) Ignition switch ON 4.5 to 5.5 V
      B39-17 (HA1A) - B39-16 (E04)
      B39-19 (HA2A) - B39-16 (E04)      		 R-L - W-B
      B-W - W-B      		 Air fuel ratio sensor heater Idling Below 3.0 V
      Ignition switch ON 11 to 14 V
      B38-1 (A1A+) - B38-12 (E1) P -BR Air fuel ratio sensor Ignition switch ON 3.3 V*
      B38-2 (A1A-) - B38-12 (E1) V - BR Air fuel ratio sensor Ignition switch ON 3.0 V*
      B38-7 (A2A+) - B38-12 (E1) Y - BR Air fuel ratio sensor Ignition switch ON 3.3 V*
      B38-8 (A2A-) - B38-12 (E1) L - BR Air fuel ratio sensor Ignition switch ON 3.0 V*
      B39-12 (HT1B) - B39-11 (E03)
      B39-13 (HT2B) - B39-11 (E03)      		 L-R - W-B
      L - W-B      		 Heated oxygen sensor heater Idling Below 3.0 V
      Ignition switch ON 11 to 14 V
      B36-2 (OX1B) - B36-1 (EX1B)
      B36-4 (OX2B) - B36-3 (EX2B)      		 W - G-B
      G - GR      		 Heated oxygen sensor Engine speed maintained at 2500 rpm for 2 minutes after warming up sensor Pulse generation (see waveform 2 in step  c)
      B39-6 (#10) - B39-14 (E01)
      B39-1 (#20) - B39-14 (E01)
      B39-7 (#30) - B39-14 (E01)
      B39-2 (#40) - B39-14 (E01)
      B39-8 (#50) - B39-14 (E01)
      B39-3 (#60) - B39-14 (E01)      		 L - W-B
      B - W-B
      R - W-B
      G - W-B
      Y - W-B
      GR - W-B      		 Fuel injector Ignition switch ON 11 to 14 V
      Idling Pulse generation (see waveform 3 in step  d)
      B37-11 (KNK1) - B37-12 (EKNK)
      B37-5 (KNK2) - B37-6 (EKN2)      		 B - W
      G - R      		 Knock sensor Engine speed maintained at 4000 rpm after warming up engine Pulse generation (see waveform 4 in step  e)
      B36-15 (VCV1) - B38-12 (E1) P-L - BR Power source for VVT sensor (specific voltage) Ignition switch ON 4.5 to 5.5 V
      B36-16 (VCV2) - B38-12 (E1) LG-B - BR Power source for VVT sensor (specific voltage) Ignition switch ON 4.5 to 5.5 V
      B36-9 (VV1+) - B36-10 (VV1-) B-W - V VVT sensor (intake side of bank 1) Idling Pulse generation
      (see waveform 5 in step  f)
      B36-12 (VV2+) - B36-11 (VV2-) G - GR VVT sensor (intake side of bank 2) Idling Pulse generation
      (see waveform 5 in step  f)
      B36-13 (EV1+) - B36-14 (EV1-) W-R - R-B VVT sensor (exhaust side of bank 1) Idling Pulse generation
      (see waveform 6 in step  g)
      B36-18 (EV2+) - B36-17 (EV2-) LG - P VVT sensor (exhaust side of bank 2) Idling Pulse generation
      (see waveform 6 in step  g)
      B36-6 (NE+) - B36-5 (NE-) B - W Crankshaft position sensor Idling Pulse generation (see waveform 5 in step  f)
      B38-24 (IGT1) - B38-12 (E1)
      B38-25 (IGT2) - B38-12 (E1)
      B38-26 (IGT3) - B38-12 (E1)
      B38-27 (IGT4) - B38-12 (E1)
      B38-28 (IGT5) - B38-12 (E1)
      B37-25 (IGT6) - B38-12 (E1)      		 R-Y - BR
      W-R - BR
      G-B - BR
      LG-B - BR
      GR - BR
      L-W - BR      		 Ignition coil (ignition signal) Idling Pulse generation (see waveform 7 in step  h)
      B38-6 (IGF1) - B38-12 (E1) G-R - BR Ignition coil (ignition confirmation signal) Ignition switch ON 4.5 to 5.5 V
      Idling Pulse generation (see waveform 7 in step  h)
      B38-18 (PRG) - B38-12 (E1) P - BR Purge VSV Ignition switch ON 11 to 14 V
      Idling Pulse generation (see waveform 8 in step  i)
      F51-18 (SPD) - B38-12 (E1) SB - BR Vehicle speed signal from combination meter Driving at 20 km/h (12 mph) Pulse generation (see waveform 9 in step  j)
      F50-10 (STA) - B38-12 (E1) W - BR Starter signal Cranking 5.5 V or higher
      B37-2 (NSW) - B38-12 (E1) B - BR Starter relay control Ignition switch ON Below 1.5 V
      Cranking 6.0 V or higher
      F50-18 (STP) - B38-12 (E1) V - BR Stop light switch Brake pedal depressed 7.5 to 14 V
      Brake pedal released Below 1.5 V
      F51-8 (ST1-) - B38-12 (E1) B - BR Stop light switch
      (opposite to voltage at STP terminal)      		 Ignition switch ON,
      brake pedal depressed      		 Below 1.5 V
      Ignition switch ON,
      brake pedal released      		 7.5 to 14 V
      B39-20 (M+) - B39-10 (ME01) P - W-B Throttle actuator Idling with warm engine Pulse generation (see waveform 10 in step  k)
      B38-29 (M-) - B39-10 (ME01) L - W-B Throttle actuator Idling with warm engine Pulse generation (see waveform 11 in step  l)
      F50-8 (FC) - B38-12 (E1) G - BR Fuel pump control Engine stopped and ignition switch ON 11 to 14 V
      Idling Below 1.5 V
      F51-3 (FPC) - B38-12 (E1) G - BR Fuel pump control Engine stopped and ignition switch ON Below 1.5 V
      F50-26 (DI) - B38-12 (E1) GR - BR Fuel pump control Engine stopped and ignition switch ON 0 to 3.0 V
      F51-13 (W) - B38-12 (E1) L - BR MIL Ignition switch ON Below 1.5 V
      Idling 11 to 14 V
      F50-28 (TC) - B38-12 (E1) R - BR Terminal TC of DLC3 Ignition switch ON 11 to 14 V
      F50-29 (TACH) - B38-12 (E1) P - BR Engine speed Idling Pulse generation (see waveform 12 in step  m)
      F50-19 (VPMP) - B38-12 (E1) L - BR Vent valve (built into canister pump module) Ignition switch ON 11 to 14 V
      F50-7 (MPMP) - B38-12 (E1) B - BR Leak detection pump (built into canister pump module) Leak detection pump off Below 3 V
      Leak detection pump on 11 to 14 V
      B36-15 (VCV1) - B37-8 (ETHW) P-L - W-R Power source for canister pressure sensor (fixed voltage) Ignition switch ON 4.5 to 5.5 V
      B37-1 (PPMP) - B37-8 (ETHW) V - W-R Canister pressure sensor (built into canister pump module) Ignition switch ON 3 to 3.6 V
      F51-10 (ELS2) - B38-12 (E1) LG - BR Electric load Vehicle stationary, voltage inverter outputs more than 100 W 11 to 14 V
      Vehicle stationary, voltage inverter outputs 100 W or less 0 to 1.5 V
      B37-28 (ALT) - B38-12 (E1) L - BR Generator Ignition switch ON 11 to 14 V
      F50-32 (CANH) - B38-12 (E1) V - BR CAN communication line Ignition switch ON Pulse generation (see waveform 13 in step  n)
      F50-31 (CANL) - B38-12 (E1) W - BR CAN communication line Ignition switch ON Pulse generation (see waveform 14 in step  o)
      F50-34 (CANP) - B38-12 (E1) R - BR CAN communication line Ignition switch ON Pulse generation (see waveform 13 in step  n)
      F50-33 (CANN) - B38-12 (E1) W - BR CAN communication line Ignition switch ON Pulse generation (see waveform 14 in step  o)
      B37-16 (PSP) - B38-12 (E1) W-G - BR Power steering oil pressure sensor Ignition switch ON 0.5 to 4.5 V
      B37-29 (NEO) - B38-12 (E1) P - BR Engine speed signal to power management control ECU Idling with warm engine Pulse generation (see waveform 15 in step  p)

      HINT: 

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

    2. Waveform 1
      Fig 2: Identifying Waveform 1
      GTY133976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      CAMSHAFT TIMING OIL CONTROL VALVE

      Symbol Between OC1+ and OC1-
      Between OC2+ and OC2-
      Between OE1+ and OE1-
      Between OE2+ and OE2-
      Tester Range 5 V/DIV., 1 msec./DIV.
      Condition Idling
    3. Waveform 2
      Fig 3: Identifying Waveform 2
      GTY136928Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      HEATED OXYGEN SENSOR

      Symbol Between OX1B and EX1B
      Between OX2B and EX2B
      Tester Range 0.2 V/DIV., 200 msec./DIV.
      Condition Engine speed maintained at 2500 rpm for 2 minutes after warming up sensor

      HINT: 

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

    4. Waveform 3
      Fig 4: Identifying Waveform 3
      GTY145152Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      FUEL INJECTOR NO. 1 (TO NO. 6) INJECTION SIGNAL

      Symbol Between #10 (to #60) and E01
      Tester Range 20 V/DIV., 20 msec./DIV.
      Condition Idling

      HINT: 

      The wavelength becomes shorter as the engine speed increases.

    5. Waveform 4
      Fig 5: Identifying Waveform 4
      GTY145057Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      KNOCK SENSOR

      Symbol Between KNK1 and EKNK
      Between KNK2 and EKN2
      Tester Range 1 V/DIV., 1 msec./DIV.
      Condition Engine speed maintained at 4000 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.
    6. Waveform 5
      Fig 6: Identifying Waveform 5
      GTY211548Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      CRANKSHAFT POSITION SENSOR AND VVT SENSOR

      Symbol Between NE+ and NE-
      Between VV1+ and VV1-
      Between VV2+ and VV2-
      Tester Range 5 V/DIV., 20 msec./DIV.
      Condition Idling

      HINT: 

      The wavelength becomes shorter as the engine speed increases.

    7. Waveform 6
      Fig 7: Identifying Waveform 6
      GTY104899Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      CRANKSHAFT POSITION SENSOR AND VVT SENSOR

      Symbol Between NE+ and NE-
      Between EV1+ and EV1-
      Between EV2+ and EV2-
      Tester Range 5 V/DIV., 20 msec./DIV.
      Condition Idling

      HINT: 

      The wavelength becomes shorter as the engine speed increases.

    8. Waveform 7
      Fig 8: Identifying Waveform 7
      GTY229904Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      IGNITER IGT SIGNAL (FROM ECM TO IGNITER) AND IGNITER IGF SIGNAL (FROM IGNITER TO ECM)

      Symbol Between IGT (1 to 6) and E1
      Between IGF1 and E1
      Tester Range 2 V/DIV., 20 msec./DIV.
      Condition Idling

      HINT: 

      The wavelength becomes shorter as the engine speed increases.

    9. Waveform 8
      Fig 9: Identifying Waveform 8
      GTY143751Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      PURGE VSV

      Symbol Between PRG and E1
      Tester Range 10 V/DIV., 20 msec./DIV.
      Condition Idling

      HINT: 

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

    10. Waveform 9
      Fig 10: Identifying Waveform 9
      GTY145136Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      VEHICLE SPEED SIGNAL

      Symbol Between SPD and E1
      Tester Range 2 V/DIV., 20 msec./DIV.
      Condition Driving at 20 km/h (12 mph)

      HINT: 

      The wavelength becomes shorter as the vehicle speed increases.

    11. Waveform 10
      Fig 11: Identifying Waveform 10
      GTY141299Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      THROTTLE ACTUATOR POSITIVE TERMINAL

      Symbol Between M+ and ME01
      Tester Range 5 V/DIV., 1 msec./DIV.
      Condition Idling with warm engine

      HINT: 

      The duty ratio varies depending on the throttle actuator operation.

    12. Waveform 11
      Fig 12: Identifying Waveform 11
      GTY135981Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      THROTTLE ACTUATOR NEGATIVE TERMINAL

      Symbol Between M- and ME01
      Tester Range 5 V/DIV., 1 msec./DIV.
      Condition Idling with warm engine

      HINT: 

      The duty ratio varies depending on the throttle actuator operation.

    13. Waveform 12
      Fig 13: Identifying Waveform 12
      GTY184266Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      ENGINE SPEED SIGNAL

      Symbol Between TACH and E1
      Tester Range 5 V/DIV., 10 msec./DIV.
      Condition Idling

      HINT: 

      The wavelength becomes shorter as the engine speed increases.

    14. Waveform 13
      Fig 14: Identifying Waveform 13
      GTY125259Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      CAN COMMUNICATION SIGNAL

      Symbol Between CANH and E1
      Between CANP and E1
      Tester Range 1 V/DIV., 10 μsec./DIV.
      Condition Engine stopped and ignition switch ON

      HINT: 

      The waveform varies depending on the CAN communication signal.

    15. Waveform 14
      Fig 15: Identifying Waveform 14
      GTY144118Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      CAN COMMUNICATION SIGNAL

      Symbol Between CANL and E1
      Between CANN and E1
      Tester Range 1 V/DIV., 10 μsec./DIV.
      Condition Engine stopped and ignition switch ON

      HINT: 

      The waveform varies depending on the CAN communication signal.

    16. Waveform 15
      Fig 16: Identifying Waveform 15
      GTY225522Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      ENGINE SPEED SIGNAL

      Symbol Between NEO and E1
      Tester Range 1 V/DIV., 2 msec./DIV.
      Condition Idling with warm engine
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