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Terminals Of ECM

Fig 1: Identifying ECM Connector Terminals
GTY144645Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT: 

Each ECM terminal's standard voltage is shown in the table below. In the table, first follow the information under "Condition". Look under "Symbols (Terminal No.)" for the terminals to be inspected. The standard voltage between the terminals is shown under "Specified Condition".

Use the illustration above as a reference for the ECM terminals.

Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
BATT (E6-4) - E1 (E3-7) B - BR Battery (for measuring battery voltage and for the ECM memory) Always 11 to 14 V
+BM (E2-5) - ME01 (E2-4) Y-B - W-B Power source of throttle motor Always 11 to 14 V
IGSW (E6-17) - E1 (E3-7) G-B - BR Ignition switch Ignition switch ON 11 to 14 V
+B (E6-6) - E1 (E3-7) B - BR Power source of ECM Ignition switch ON 11 to 14 V
+B1 (E6-5) - E1 (E3-7) B-W - BR Power source of ECM Ignition switch ON 11 to 14 V
VC (E2-29) - E2 (E2-28) L-R - BR Power source of sensor
(specific voltage)		 Ignition switch ON 4.5 to 5.5 V
VTA (E2-23) - E2 (E2-28) Y - BR Throttle position sensor
(for engine control)		 Ignition switch ON, accelerator pedal fully released 0.5 to 1.1 V
VTA (E2-23) - E2 (E2-28) Y - BR Throttle position sensor
(for engine control)		 Ignition switch ON, accelerator pedal fully depressed 3.2 to 4.8 V
VTA2 (E2-22) - E2 (E2-28) L-B - BR Throttle position sensor
(for sensor malfunction detection)		 Ignition switch ON, accelerator pedal fully released 2.1 to 3.1 V
VTA2 (E2-22) - E2 (E2-28) L-B - BR Throttle position sensor
(for sensor malfunction detection)		 Ignition switch ON, accelerator pedal fully depressed 4.5 to 5.5 V
VPA (E5-33) - EPA (E5-34) R-Y - BR Accelerator pedal position sensor
(for engine control)		 Ignition switch ON, accelerator pedal fully released 0.5 to 1.1 V
VPA (E5-33) - EPA (E5-34) R-Y - BR Accelerator pedal position sensor
(for engine control)		 Ignition switch ON, accelerator pedal fully depressed 2.6 to 4.5 V
VPA2 (E5-32) - EPA2 (E5-26) B-W - G Accelerator pedal position sensor
(for sensor malfunction detection)		 Ignition switch ON, accelerator pedal fully released 1.2 to 2.0 V
VPA2 (E5-32) - EPA2 (E5-26) B-W - G Accelerator pedal position sensor
(for sensor malfunction detection)		 Ignition switch ON, accelerator pedal fully depressed 3.4 to 5.3 V
VCPA (E5-35) - EPA (E5-34) L-R - BR Power source of accelerator pedal position sensor (for VPA) Ignition switch ON 4.5 to 5.5 V
VCP2 (E5-27) - EPA2 (E5-26) G-W - G Power source of accelerator pedal position sensor (for VPA2) Ignition switch ON 4.5 to 5.5 V
VG (E4-27) - E2G (E4-26) B-R - B-W MAF meter Idling, shift position P or N, A/C switch off 0.5 to 3.0 V
THA (E4-25) - E2 (E2-28) B-L - BR IAT sensor Idling, IAT: 0 to 80°C (32 to 176°F) after warm-up 0.5 to 3.4 V
THW (E4-20) - E2 (E2-28) R-L - BR ECT sensor Idling, ECT: 60 to 100°C (140 to 212°F) after warm-up 0.2 to 1.0 V
STA (E6-12) - E1 (E3-7) W-L - BR Starter signal Cranking (shift position P or N position and ignition switch start) 6 V or more
#1 (E2-15) - E01 (E4-2)
#2 (E4-17) - E01 (E4-2)
#3 (E2-14) - E01 (E4-2)
#4 (E4-16) - E01 (E4-2)
#5 (E2-13) - E01 (E4-2)
#6 (E4-15) - E01 (E4-2)
#7 (E2-12) - E01 (E4-2)
#8 (E4-14) - E01 (E4-2)		 L - W-B
W - W-B
G-Y - W-B
G - W-B
G - W-B
BR - W-B
BR - W-B
Y-B - W-B		 Injector Idling Pulse generation
(see Fig 2 waveform 1)
#1 (E2-15) - E01 (E4-2)
#2 (E4-17) - E01 (E4-2)
#3 (E2-14) - E01 (E4-2)
#4 (E4-16) - E01 (E4-2)
#5 (E2-13) - E01 (E4-2)
#6 (E4-15) - E01 (E4-2)
#7 (E2-12) - E01 (E4-2)
#8 (E4-14) - E01 (E4-2)		 L - W-B
W - W-B
G-Y - W-B
G - W-B
G - W-B
BR - W-B
BR - W-B
Y-B - W-B		 Injector Ignition switch ON 11 to 14 V
IGT1 (E2-17) - E1 (E3-7)
IGT2 (E4-13) - E1 (E3-7)
IGT3 (E2-16) - E1 (E3-7)
IGT4 (E4-12) - E1 (E3-7)
IGT5 (E2-27) - E1 (E3-7)
IGT6 (E4-11) - E1 (E3-7)
IGT7 (E2-26) - E1 (E3-7)
IGT8 (E4-10) - E1 (E3-7)		 G-W - BR
L-R - BR
L-Y - BR
LG - BR
R - BR
R-L - BR
P-L - BR
B-W - BR		 Ignition coil and igniter
(ignition signal)		 Idling Pulse generation
(see Fig 3 waveform 2)
IGF1 (E4-7) - E1 (E3-7)
IGF2 (E4-6) - E1 (E3-7)		 LG - BR
G-B - BR		 Ignition coil and igniter
(ignition confirmation signal)		 Idling Pulse generation
(see Fig 3 waveform 2)
IGF1 (E4-7) - E1 (E3-7)
IGF2 (E4-6) - E1 (E3-7)		 LG - BR
G-B - BR		 Ignition coil and igniter
(ignition confirmation signal)		 Ignition switch ON 4.5 to 5.5 V
G2 (E2-21) - G2- (E2-20) L - Y Camshaft position sensor Idling Pulse generation
(see Fig 4 waveform 3)
NE+ (E2-32) - NE- (E2-31) B - W Crankshaft position sensor Idling Pulse generation
(see Fig 4 waveform 3 and Fig 9 8)
MREL (E6-13) - E1 (E3-7) G-O - BR EFI relay Ignition switch ON 11 to 14 V
MREL (E6-13) - E1 (E3-7) G-O - BR EFI relay Ignition switch OFF (for 3 seconds or more) Below 1.5 V
FPR (E6-15) - E01 (E4-2) LG - W-B Fuel pump relay Ignition switch ON Below 3 V
FPR (E6-15) - E01 (E4-2) LG - W-B Fuel pump relay Cranking 6 to 14 V
FC (E6-14) - E01 (E4-2) BE - W-B Fuel pump control Ignition switch ON 11 to 14 V
FC (E6-14) - E01 (E4-2) BE - W-B Fuel pump control Idling after engine warm-up Below 3 V
STP (E5-4) - E1 (E3-7) G-R - BR Stop light switch Brake pedal is depressed 7.5 to 14 V
STP (E5-4) - E1 (E3-7) G-R - BR Stop light switch Brake pedal is released Below 1.5 V
ST1- (E6-8) - E1 (E3-7) Y-G - BR Stop light switch
(opposite to STP terminal)		 Ignition switch ON, brake pedal is released
Ignition switch ON
Brake pedal is depressed		 Below 1.5 V
ST1- (E6-8) - E1 (E3-7) Y-G - BR Stop light switch
(opposite to STP terminal)		 Ignition switch ON, brake pedal is released 7.5 to 14 V
PRG (E2-11) - E01 (E4-2) G-B - W-B Purge VSV Ignition switch ON and engine stopped 11 to 14 V
PRG (E2-11) - E01 (E4-2) G-B - W-B Purge VSV Idling after engine warm-up Pulse generation
(see Fig 5 waveform 4)
OX1A (E2-30) - O1A- (E2-25) B - BR Heated oxygen sensor
(bank 1 sensor 1)		 Idling 0.1 to 0.9 V
Pulse generation
(see Fig 6waveform 5)
OX2A (E4-28) - O2A- (E4-21) W - BR Heated oxygen sensor
(bank 2 sensor 1)		 Idling 0.1 to 0.9 V
Pulse generation
(see Fig 6waveform 5)
OX1B (E5-28) - O1B- (E5-29) B - BR-W Heated oxygen sensor
(bank 1 sensor 2)		 Idling 0.1 to 0.9 V
Pulse generation
(see Fig 7waveform 6)
OX2B (E5-17) - O2B- (E5-18) W - BR Heated oxygen sensor
(bank 2 sensor 2)		 Idling 0.1 to 0.9 V
Pulse generation
(see Fig 7waveform 6)
HT1A (E2-24) - E03 (E2-6)
HT1B (E5-2) - E03 (E2-6)
HT2A (E4-5) - E03 (E2-6)
HT2B (E5-1) - E03 (E2-6)		 L-Y - W-B
GR-L - W-B
G-Y - W-B
GR - W-B		 Heated oxygen sensor heater Idling Below 3.0 V
HT1A (E2-24) - E03 (E2-6)
HT1B (E5-2) - E03 (E2-6)
HT2A (E4-5) - E03 (E2-6)
HT2B (E5-1) - E03 (E2-6)		 L-Y - W-B
GR-L - W-B
G-Y - W-B
GR - W-B		 Heated oxygen sensor heater Ignition switch ON 11 to 14 V
KNK1 (E3-28) - EKNK (E3-30) W - B Knock sensor
(bank 1)		 Maintain engine RPM at 4,000 RPM after engine warmed-up Pulse generation
(see Fig 8waveform 7)
KNK2 (E3-29) - EKN2 (E3-31) R - G Knock sensor
(bank 2)		 Maintain engine RPM at 4,000 RPM after engine warmed-up Pulse generation
(see Fig 8waveform 7)
TC (E5-3) - E1 (E3-7) P-B - BR Terminal TC of DLC3 Ignition switch ON 11 to 14 V
W (E5-8) - E1 (E3-7) R-B - BR MIL Idling 11 to 14 V
W (E5-8) - E1 (E3-7) R-B - BR MIL Ignition switch ON Below 3.0 V
VV1+ (E2-19) - VV1- (E2-18) R - G Variable Valve Timing (VVT) sensor
(bank 1)		 Idling Pulse generation
(see Fig 9waveform 8)
VV2+ (E4-19) - VV2- (E4-18) Y - L VVT sensor (bank 2) Idling Pulse generation
(see Fig 9waveform 8)
OC1+ (E2-34) - OC1- (E2-33) L-Y - G-W Camshaft timing control valve (OCV)
(bank 1)		 Accelerate slowly after engine warmed-up Pulse generation
(see Fig 10waveform 9)
OC2+ (E4-9) - OC2- (E4-8) L-W - L-B OCV (bank 2) Accelerate slowly after engine warmed-up Pulse generation
(see Fig 10waveform 9)
TACH (E5-16) - E1 (E3-7) B-Y - BR Engine speed Idling Pulse generation
(see Fig 11waveform 10)
ACIS (E4-3) - E01 (E4-2) L-W - W-B Vacuum switching valve (for ACIS) Ignition switch ON 11 to 14 V
ACIS (E4-3) - E01 (E4-2) L-W - W-B Vacuum switching valve (for ACIS) Engine RPM: 2,500 to 4,000 RPM and throttle opening angle: 40% or more Below 3.0 V
M+ (E2-2) - ME01 (E2-4) B - W-B Throttle actuator Idling Pulse generation
(see Fig 12waveform 11)
M- (E2-1) - ME01 (E2-4) W - W-B Throttle actuator Idling Pulse generation
(see Fig 13waveform 12)
SPD (E6-22) - E1 (E3-7) W-R - BR Speed signal from combination meter Ignition switch ON, rotate driving wheel slowly Pulse generation
(see Fig 14waveform 13)
RFC (E6-10) - E1 (E3-7) Y - BR Cooling fan ECU Ignition switch ON 0 to 3 V
E1 (E3-7) - Body ground BR - N/A Ground Always Below 1 Ω
VPMP (E5-12) - E1 (E3-7) BE - BR Vent valve
(built into pump module)		 Ignition switch ON 11 to 14 V
MPMP (E5-5) - E1 (E3-7) G-Y - BR Vacuum pump
(built into pump module)		 Vacuum pump off 0 to 3 V
MPMP (E5-5) - E1 (E3-7) G-Y - BR Vacuum pump
(built into pump module)		 Vacuum pump on 11 to 14 V
PPMP (E5-25) - E1 (E3-7) BR-W - BR Pressure sensor
(built into pump module)		 Ignition switch ON 3 to 3.6 V
CANH (E6-25) - E1 (E3-7) R - BR CAN communication line Ignition switch ON Pulse generation
(see Fig 15waveform 14)
CANL (E6-24) - E1 (E3-7) W - BR CAN communication line Ignition switch ON Pulse generation
(see Fig 16waveform 15)
  1. WAVEFORM 1 
    Fig 2: Identifying Waveform 1
    GTY132785Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Fuel injector
    Item Content
    Symbols (Terminal No.) #1 (E2-15) - E01 (E4-2)
    #2 (E4-17) - E01 (E4-2)
    #3 (E2-14) - E01 (E4-2)
    #4 (E4-16) - E01 (E4-2)
    #5 (E2-13) - E01 (E4-2)
    #6 (E4-15) - E01 (E4-2)
    #7 (E2-12) - E01 (E4-2)
    #8 (E4-14) - E01 (E4-2)
    Tool Setting 20 V/DIV., 20 msec./DIV.
    Condition Idling

    HINT: 

    The wavelength becomes shorter as engine RPM increases.

  2. WAVEFORM 2 
    Fig 3: Identifying Waveform 2 (Igniter IGT Signal)
    GTY145150Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • (a) Igniter IGT signal (from ECM to igniter)

      (b) Igniter IGF signal (from igniter to ECM)

    Item Content
    Symbols (Terminal No.) (a) IGT1 (E2-17) - E1 (E3-7)
    (a) IGT2 (E4-13) - E1 (E3-7)
    (a) IGT3 (E2-16) - E1 (E3-7)
    (a) IGT4 (E4-12) - E1 (E3-7)
    (a) IGT5 (E2-27) - E1 (E3-7)
    (a) IGT6 (E4-11) - E1 (E3-7)
    (a) IGT7 (E2-26) - E1 (E3-7)
    (a) IGT8 (E4-10) - E1 (E3-7)
    (b) IGF1 (E4-7) - E1 (E3-7)
    (b) IGF2 (E4-6) - E1 (E3-7)
    Tool Setting 2 V/DIV., 20 msec./DIV.
    Condition Idling

    HINT: 

    The wavelength becomes shorter as engine RPM increases.

  3. WAVEFORM 3 
    Fig 4: Identifying Waveform 3 Camshaft Position Sensor
    GTY145149Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • (a) Camshaft position sensor

      (b) Crankshaft position sensor

    Item Content
    Symbols (Terminal No.) (a) G2 (E2-21) - G2- (E2-20)
    (b) NE+ (E2-32) - NE- (E2-31)
    Tool Setting 5 V/DIV., 20 msec./DIV.
    Condition Idle after engine warmed-up

    HINT: 

    The wavelength becomes shorter as engine RPM increases.

  4. WAVEFORM 4 
    Fig 5: Identifying Waveform 4 VSV (For EVAP)
    GTY125126Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Purge VSV
    Item Content
    Symbols (Terminal No.) PRG (E2-11) - E01 (E4-2)
    Tool Setting 5 V/DIV., 150 msec./DIV.
    Condition Accelerated slowly after engine warmed-up

    HINT: 

    In cases where the purge VSV can be used to purge the EVAP, the waveform will not be displayed as shown in the illustration. In the Data List, the item Purge VSV shows the duty ratio of voltage flowing to the purge valve.

    Duty ratio for purge VSV (%) = A/B x 100

  5. WAVEFORM 5 
    Fig 6: Identifying Waveform 5 Heated Oxygen Sensor
    GTY135950Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Heated oxygen sensor (sensor 1)
    Item Content
    Symbols (Terminal No.) OX1A (E2-30) - O1A- (E2-25)
    OX2A (E4-28) - O2A- (E4-21)
    Tool Setting 0.2 V/DIV., 200 msec./DIV.
    Condition Maintain engine speed at 2,500 RPM after engine warmed up

    HINT: 

    In the Data List, the items heated oxygen sensor B1 S1 and heated oxygen sensor B2 S1 show the ECM input values of the heated oxygen sensor (sensor 1).

  6. WAVEFORM 6 
    Fig 7: Identifying Waveform 6 (Heated Oxygen Sensor)
    GTY145094Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Heated oxygen sensor (sensor 2)
    Item Content
    Symbols (Terminal No.) OX1B (E5-28) - O1B- (E5-29)
    OX2B (E5-17) - O2B- (E5-18)
    Tool Setting 0.2 V/DIV., 200 msec./DIV.
    Condition Maintain engine speed at 2,500 RPM after engine warmed up

    HINT: 

    In the Data List, the items heated oxygen sensor B1 S2 and heated oxygen sensor B2 S2 show the ECM input values of the heated oxygen sensor (sensor 2).

  7. WAVEFORM 7 
    Fig 8: Identifying Waveform 7 Knock Sensor
    GTY145038Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Knock sensor
    Item Content
    Symbols (Terminal No.) KNK1 (E3-28) - EKNK (E3-30)
    KNK2 (E3-29) - EKN2 (E3-31)
    Tool Setting 1 V/DIV., 1 msec./DIV.
    Condition Maintain engine speed at 2,000 RPM after engine warmed-up

    HINT: 

    • The wavelength becomes shorter as engine RPM increases.
    • The waveforms and amplitude displayed differ slightly depending on the vehicle.
  8. WAVEFORM 8 
    Fig 9: Identifying Waveform 8
    GTY130298Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • (a) VVT sensor bank 1

      (b) VVT sensor bank 2

      (c) Crankshaft position sensor

    Item Content
    Symbols (Terminal No.) (a) VV1+ (E2-19) - VV1- (E2-18)
    (b) VV2+ (E4-19) - VV2- (E4-18)
    (c) NE+ (E2-32) - NE- (E2-31)
    Tool Setting 2 V/DIV., 20 msec./DIV.
    Condition Idle after engine warmed-up

    HINT: 

    The wavelength becomes shorter as engine RPM increases.

  9. WAVEFORM 9 
    Fig 10: Identifying Waveform 9
    GTY145142Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • VVT OCV
    Item Content
    Symbols (Terminal No.) OC1+ (E2-34) - OC1- (E2-33)
    OC2+ (E4-9) - OC2- (E4-8)
    Tool Setting 5 V/DIV., 1 msec./DIV.
    Condition Idling
  10. WAVEFORM 10 
    Fig 11: Identifying Waveform 10 (Engine Speed Signal)
    GTY145140Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Engine speed signal
    Item Content
    Symbols (Terminal No.) TACH (E5-16) - E1 (E3-7)
    Tool Setting 5 V/DIV., 10 msec./DIV.
    Condition Idling

    HINT: 

    The wavelength becomes shorter as the engine RPM increases.

  11. WAVEFORM 11 
    Fig 12: Identifying Waveform 11 (Throttle Actuator Positive Terminal)
    GTY144504Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Throttle actuator positive terminal
    Item Content
    Symbols (Terminal No.) M+ (E2-2) - ME01 (E2-4)
    Tool Setting 5 V/DIV., 1 msec./DIV.
    Condition Idle after engine warmed-up

    HINT: 

    The duty ratio varies depending on the throttle opening operation.

  12. WAVEFORM 12 
    Fig 13: Identifying Waveform 12
    GTY145146Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Throttle actuator negative terminal
    Item Content
    Symbols (Terminal No.) M- (E2-1) - ME01 (E2-4)
    Tool Setting 5 V/DIV., 1 msec./DIV.
    Condition Idle after engine warmed-up

    HINT: 

    The duty ratio varies depending on the throttle opening operation.

  13. WAVEFORM 13 
    Fig 14: Identifying Waveform 13 (Vehicle Speed Signal)
    GTY145137Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Vehicle speed signal
    Item Content
    Symbols (Terminal No.) SPD (E6-22) - E1 (E3-7)
    Tool Setting 2 V/DIV., 20 msec./DIV.
    Condition Driving at 20 km/h (12 mph)

    HINT: 

    The wavelength becomes shorter as vehicle speed increases.

  14. WAVEFORM 14 
    Fig 15: Identifying Waveform 14
    GTY141831Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • CAN communication signal
    Item Content
    Symbols (Terminal No.) CANH (E6-25) - E1 (E3-7)
    Tool Setting 1 V/DIV., 10 μsec./DIV.
    Condition Stop engine and ignition switch ON

    HINT: 

    The waveform varies depending on the CAN communication signal.

  15. WAVEFORM 15 
    Fig 16: Identifying Waveform 15
    GTY138994Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • CAN communication signal
    Item Content
    Symbols (Terminal No.) CANL (E6-24) - E1 (E3-7)
    Tool Setting 1 V/DIV., 10 μsec./DIV.
    Condition Stop engine and ignition switch ON

    HINT: 

    The waveform varies depending on the CAN communication signal.

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