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Terminals Of ECM

Fig 1: ECM Connector Terminal Identification - SFI System
GTY237080Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT: 

The standard normal 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 normal 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.

Symbol (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
BATT (A21-20) - E1 (C20-104) Y - W Battery (for measuring battery voltage and for ECM memory) Always 11 to 14 V
+BM (A21-3) - ME01 (C20-43) GR - BR Power source of throttle actuator Always 11 to 14 V
IGSW (A21-28) - E1 (C20-104) R - W Ignition switch Ignition switch ON 11 to 14 V
+B (A21-2) - E1 (C20-104) B - W Power source of ECM Ignition switch ON 11 to 14 V
+B2 (A21-1) - E1 (C20-104) B - W Power source of ECM Ignition switch ON 11 to 14 V
OC1+ (C20-100) - OC1- (C20-123) BR - R Camshaft timing oil control valve (OCV) Idling Pulse generation (SeeFig 2 waveform 1)
MREL (A21-44) - E1 (C20-104) GR - W EFI relay Ignition switch ON 11 to 14 V
VG (C20-118) - E2G (C20-116) GR - LG Mass air flow meter Idling, Transmission gear neutral, A/C switch OFF 0.5 to 3.0 V
THA (C20-65) - ETHA (C20-88) P - BE Intake air temperature sensor Idling, Intake air temperature 20°C (68°F) 0.5 to 3.4 V
THW (C20-97) - ETHW (C20-96) L - P Engine coolant temperature sensor Idling, Engine coolant temperature 80°C (176°F) 0.2 to 1.0 V
VCTA (C20-67) - ETA (C20-91) W - V Power source of throttle position sensor (specific voltage) Ignition switch ON 4.5 to 5.5 V
VTA1 (C20-115) - ETA (C20-91) Y - V 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
3.2 to 4.8 V
VTA2 (C20-114) - ETA (C20-91) GR - V 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
VPA (A21-55) - EPA (A21-59) 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
VPA2 (A21-56) - EPA2 (A21-60) 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
VCPA (A21-57) - EPA (A21-59) B - G Power source of accelerator pedal position sensor (for VPA) Ignition switch ON 4.5 to 5.5 V
VCP2 (A21-58) - EPA2 (A21-60) W - BR Power source of accelerator pedal position sensor (for VPA2) Ignition switch ON 4.5 to 5.5 V
HA1A (C20-109) - E04 (C20-46) G - W-B A/F sensor heater Idling with warm engine Pulse generation (SeeFig 3waveform 2)
Ignition switch ON 11 to 14 V
A1A+ (C20-112) - E1 (C20-104) V -W A/F sensor Ignition switch ON 3.3 V*
A1A- (C20-113) - E1 (C20-104) LG - W A/F sensor Ignition switch ON 2.9 V*
HT1B (C20-47) - E03 (C20-86) LG - W-B Heated oxygen sensor heater Idling Below 3.0 V
Ignition switch ON 11 to 14 V
OX1B (C20-64) - EX1B (C20-87) G - GR Heated oxygen sensor Engine speed maintained at 2500 rpm for 2 minutes after warming up sensor Pulse generation (See Fig 4waveform 3)
#10 (C20-108) - E01 (C20-45)
#20 (C20-107) - E01 (C20-45)
#30 (C20-106) - E01 (C20-45)
#40 (C20-105) - E01 (C20-45)
SB - BR
GR - BR
P - BR
L - BR
Fuel injector Ignition switch ON 11 to 14 V
Idling Pulse generation (SeeFig 5 waveform 4)
KNK1 (C20-110) - EKNK (C20-111) R - G Knock sensor Engine speed maintained at 4000 after warming up engine Pulse generation (SeeFig 6 waveform 5)
G2+ (C20-99) - NE- (C20-121) B - P Camshaft position sensor Idling Pulse generation (See Fig 7waveform 6)
NE+ (C20-122) - NE- (C20-121) L - P Crankshaft position sensor Idling Pulse generation (See Fig 7waveform 6)
IGT1 (C20-85) - E1 (C20-104)
IGT2 (C20-84) - E1 (C20-104)
IGT3 (C20-83) - E1 (C20-104)
IGT4 (C20-82) - E1 (C20-104)
W - W
BE - W
G - W
LG - W
Ignition coil (ignition signal) Idling Pulse generation (See Fig 8waveform 7)
IGF1 (C20-81) - E1 (C20-104) Y - W Ignition coil (ignition confirmation signal) Ignition switch ON 4.5 to 5.5 V
Idling Pulse generation (See Fig 8waveform 7)
PRG (C20-49) - E01 (C20-45) L - BR Purge VSV Ignition switch ON 11 to 14 V
Idling, during purge control Pulse generation (See Fig 9waveform 8)
SPD (A21-8) - E1 (C20-104) V - W Speed signal from combination meter Driving at 20 km/h (12 mph) Pulse generation (SeeFig 10 waveform 9)
STA (A21-48) - E1 (C20-104) BR - W Starter signal Cranking 11 to 14 V
STAR (C20-52) - E1 (C20-104) BE - W Starter relay control Ignition switch ON, Shift position P or N (for A/T), Clutch pedal fully depressed (for M/T) Below 1.5 V
Cranking 6.0 V or more
ACCR (A21-13) - E01 (C20-45) G - BR ACC (Accessory) relay control signal Cranking Below 1.5 V
STSW (A21-14) - E1 (C20-104) B - W Ignition switch signal Ignition switch START position 6.0 V or more
STP (A21-36) - E1 (C20-104) G - W Stop light switch Brake pedal depressed 7.5 to 14 V
Brake pedal released Below 1.5 V
ST1- (A21-35) - E1 (C20-104) Y - W Stop light switch
(opposite to STP terminal)
Ignition switch ON,
Brake pedal depressed
Below 1.5 V
Ignition switch ON,
Brake pedal released
7.5 to 14 V
M+ (C20-42) - ME01 (C20-43) G - BR Throttle actuator Idling with warm engine Pulse generation (See Fig 11waveform 10)
M- (C20-41) - ME01 (C20-43) R - BR Throttle actuator Idling with warm engine Pulse generation (SeeFig 12 waveform 11)
FC (A21-7) - E01 (C20-45) V - BR Fuel pump control Ignition switch ON 11 to 14 V
Idling Below 1.5 V
W (A21-24) - E1 (C20-104) B - W MIL Ignition switch ON (MIL goes on) Below 1.5 V
Idling (MIL goes off) 11 to 14 V
TC (A21-27) - E1 (C20-104) P - W Terminal TC of DLC 3 Ignition switch ON 11 to 14 V
TACH (A21-15) - E1 (C20-104) LG - W Engine speed Idling Pulse generation (SeeFig 13 waveform 12)
VPMP (A21-42) - E1 (C20-104) P - W Vent valve (built into canister pump module) Ignition switch ON 11 to 14 V
MPMP (A21-34) - E1 (C20-104) 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
VCPP (C20-70) - EPPM (C20-94) V - BE Power source for canister pressure sensor (specific voltage) Ignition switch ON 4.5 to 5.5 V
PPMP (C20-71) - EPPM (C20-94) L - BE Canister pressure sensor (built into canister pump module) Ignition switch ON 3 to 3.6 V
ELS (A21-31) - E1 (C20-104) G - W Electric load Tail light switch ON 7.5 to 14 V
Tail light switch OFF Below 1.5 V
ELS3 (A21-33) - E1 (C20-104) V - W Electric load Defogger switch ON 7.5 to 14 V
Defogger switch OFF Below 1.5 V
FAN (A21-21) - E1 (C20-104) BE - W Fan No. 1 relay Ignition switch ON 11 to 14 V
Idling with A/C ON, or high engine coolant temperature Below 1.5 V
FAN2 (A21-22) - E1 (C20-104) LG - W Fan No. 2 relay Idling with high engine coolant temperature Below 1.5 V
ALT (C20-50) - E1 (C20-104) P - W Generator Ignition switch ON 11 to 14 V
CANH (A21-41) - E1 (C20-104) L - W CAN communication line Ignition switch ON Pulse generation (SeeFig 14 waveform 13)
CANL (A21-49) - E1 (C20-104) W - W CAN communication line Ignition switch ON Pulse generation (SeeFig 15 waveform 14)

HINT: 

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

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

    ECM Terminal Names Between OC1+ and OC1-
    Tester Ranges 5 V/DIV, 1 msec./DIV
    Conditions Idling
  2. WAVEFORM 2 
    Fig 3: Identifying Waveform 2
    GTY216533Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    AIR-FUEL RATIO SENSOR HEATER

    ECM Terminal Names Between HA1A and E04
    Tester Ranges 5 V/DIV, 10 msec./DIV
    Conditions Idling with warm engine

    HINT: 

    The wavelength varies in accordance with the engine operating condition.

  3. WAVEFORM 3 
    Fig 4: Identifying Waveform 3
    GTY136928Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    HEATED OXYGEN SENSOR

    ECM Terminal Names Between OX1B and EX1B
    Tester Ranges 0.2 V/DIV, 200 msec./DIV
    Conditions Engine speed maintained at 2500 rpm for 2 minutes after warming up sensor

    HINT: 

    In DATA LIST, item O2S B1S2 shows the ECM input values from the heated oxygen sensor.

  4. WAVEFORM 4 
    Fig 5: Identifying Waveform 4
    GTY145152Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    FUEL INJECTOR NO. 1 (TO NO. 4) INJECTION SIGNAL

    ECM Terminal Names Between #10 (to #40) and E01
    Tester Ranges 20 V/DIV, 20 msec./DIV
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  5. WAVEFORM 5 
    Fig 6: Identifying Waveform 5
    GTY224402Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    KNOCK SENSOR

    ECM Terminal Names Between KNK1 and EKNK
    Tester Ranges 500 mV/DIV, 1 msec./DIV
    Conditions Engine speed maintained at 4000 rpm after warming up engine

    HINT: 

    • The waveforms and amplitudes displayed differ slightly depending on the vehicle.
  6. WAVEFORM 6 
    Fig 7: Identifying Waveform 6
    GTY236943Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CRANKSHAFT POSITION SENSOR AND CAMSHAFT POSITION SENSOR

    ECM Terminal Names CH1: Between G2+ and NE-
    CH2: Between NE+ and NE-
    Tester Ranges 5 V/DIV, 20 msec./DIV
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  7. WAVEFORM 7 
    Fig 8: Identifying Waveform 7
    GTY294069Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    IGNITER IGT SIGNAL (FROM ECM TO IGNITER) AND IGNITER IGF SIGNAL (FROM IGNITER TO ECM)

    ECM Terminal Names Between IGT (1 to 4) and E1
    Between IGF1 and E1
    Tester Ranges 2 V/DIV, 20 msec./DIV
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  8. WAVEFORM 8 
    Fig 9: Identifying Waveform 8
    GTY226842Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    PURGE VSV

    ECM Terminal Names Between PRG and E01
    Tester Ranges 10 V/DIV, 20 msec./DIV
    Conditions Idling, during purge control

    HINT: 

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

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

    ECM Terminal Names Between SPD and E1
    Tester Ranges 2 V/DIV, 20 msec./DIV
    Conditions Driving at 20 km/h (12 mph)

    HINT: 

    The wavelength becomes shorter as the vehicle speed increases.

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

    ECM Terminal Names Between M+ and ME01
    Tester Ranges 5 V/DIV, 1 msec./DIV
    Conditions Idling with warm engine

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

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

    ECM Terminal Names Between M- and ME01
    Tester Ranges 5 V/DIV, 1 msec./DIV
    Conditions Idling with warm engine

    HINT: 

    The duty ratio varies depending on the throttle actuator operation.

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

    ECM Terminal Names Between TACH and E1
    Tester Ranges 5 V/DIV, 10 msec./DIV
    Conditions Idling

    HINT: 

    The wavelength becomes shorter as the engine rpm increases.

  13. WAVEFORM 13 
    Fig 14: Identifying Waveform 13
    GTY136819Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    REFERENCE: CAN COMMUNICATION SIGNAL

    ECM Terminal Names Between CANH and E1
    Tester Ranges 1 V/DIV, 10 μsec./DIV.
    Conditions Engine stops and ignition switch ON

    HINT: 

    The waveform varies depending on the CAN communication signal.

  14. WAVEFORM 14 
    Fig 15: Identifying Waveform 14
    GTY145068Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    REFERENCE: CAN COMMUNICATION SIGNAL

    ECM Terminal Names Between CANL and E1
    Tester Ranges 1 V/DIV, 10 μsec./DIV.
    Conditions Engine stops and ignition switch ON

    HINT: 

    The waveform varies depending on the CAN communication signal.