SFI SYSTEM TERMINALS OF ECM
Tech Tips
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 |
|---|---|---|---|---|
| A74-20 (BATT) - E83-104 (E1) | GR - BR | Battery (for measuring battery voltage and for ECM memory) | Always | 11 to 14 V |
| A74-3 (+BM) - E83-104 (E1) | LG - BR | Power source of throttle actuator | Always | 11 to 14 V |
| A74-28 (IGSW) - E83-104 (E1) | V - BR | Ignition switch signal | Ignition switch ON | 11 to 14 V |
| A74-2 (+B) - E83-104 (E1) | P - BR | Power source of ECM | Ignition switch ON | 11 to 14 V |
| A74-1 (+B2) - E83-104 (E1) | LG - BR | Power source of ECM | Ignition switch ON | 11 to 14 V |
| E83-100 (OC1+) - E83-123 (OC1-) | W - B | Camshaft timing oil control valve assembly operation signal | Idling | Pulse generation (See waveform 1) |
| A74-44 (MREL) - E83-104 (E1) | BE - BR | EFI MAIN relay operation signal | Ignition switch ON | 11 to 14 V |
| E83-118 (VG) - E83-116 (E2G) | L - W | Mass air flow meter sub-assembly signal | Idling, shift lever in P, A/C switch off | 0.5 to 3.0 V |
| E83-65 (THA) - E83-88 (ETHA) | P - Y | Intake air temperature sensor signal | Idling, intake air temperature 20°C (68°F) | 0.5 to 3.4 V |
| E83-97 (THW) - E83-96 (ETHW) | B - P | Engine coolant temperature sensor signal | Idling, engine coolant temperature 80°C (176°F) | 0.2 to 1.0 V |
| E83-67 (VCTA) - E83-91 (ETA) | B - R | Power source of throttle position sensor (specific voltage) | Ignition switch ON | 4.5 to 5.5 V |
| E83-115 (VTA1) - E83-91 (ETA) | Y - R | Throttle position sensor signal (for engine control) | Ignition switch ON, accelerator pedal fully released |
0.5 to 1.1 V |
| Ignition switch ON, accelerator pedal fully depressed |
3.2 to 4.8 V | |||
| E83-114 (VTA2) - E83-91 (ETA) | L - R | Throttle position sensor signal (for sensor malfunction detection) | Ignition switch ON, accelerator pedal fully released |
2.1 to 3.1 V |
| Ignition switch ON, accelerator pedal fully depressed |
4.6 to 5.0 V | |||
| A74-55 (VPA) - A74-59 (EPA) | G - Y | Accelerator pedal position sensor signal (for engine control) | Ignition switch ON, accelerator pedal fully released |
0.5 to 1.1 V |
| Ignition switch ON, accelerator pedal fully depressed |
2.6 to 4.5 V | |||
| A74-56 (VPA2) - A74-60 (EPA2) | R - BE | Accelerator pedal position sensor signal | Ignition switch ON, accelerator pedal fully released |
1.2 to 2.0 V |
| Ignition switch ON, accelerator pedal fully depressed |
3.4 to 4.75 V | |||
| A74-57 (VCPA) - A74-59 (EPA) | P - Y | Power source of accelerator pedal position sensor (for VPA) | Ignition switch ON | 4.5 to 5.5 V |
| A74-58 (VCP2) - A74-60 (EPA2) | L - BE | Power source of accelerator pedal position sensor (for VPA2) | Ignition switch ON | 4.5 to 5.5 V |
| E83-109 (HA1A) - E83-46 (E04) | G - W-B | Air fuel ratio sensor (sensor 1) heater operation signal | Idling | Pulse generation (See waveform 2) |
| Ignition switch ON | 11 to 14 V | |||
| E83-112 (A1A+) - E83-104 (E1) | L - BR | Air fuel ratio sensor (sensor 1) signal | Ignition switch ON | 3.3 V*1 |
| E83-113 (A1A-) - E83-104 (E1) | P - BR | Air fuel ratio sensor (sensor 1) signal | Ignition switch ON | 2.9 V*1 |
| E83-47 (HT1B) - E83-46 (E04) | LG - W-B | Heated oxygen sensor (sensor 2) heater operation signal | Idling | Below 3.0 V |
| Ignition switch ON | 11 to 14 V | |||
| E83-64 (OX1B) - E83-87 (EX1B) | W - B | Heated oxygen sensor (sensor 2) signal | Engine speed maintained at 2500 rpm for 2 minutes after warming up engine | Pulse generation (See waveform 3) |
| E83-108 (#10) - E83-45 (E01) | B - W-B | No. 1 fuel injector assembly signal | Ignition switch ON | 11 to 14 V |
| Idling | Pulse generation (See waveform 4) |
|||
| E83-107 (#20) - E83-45 (E01) | R - W-B | No. 2 fuel injector assembly signal | Ignition switch ON | 11 to 14 V |
| Idling | Pulse generation (See waveform 4) |
|||
| E83-106 (#30) - E83-45 (E01) | Y - W-B | No. 3 fuel injector assembly signal | Ignition switch ON | 11 to 14 V |
| Idling | Pulse generation (See waveform 4) |
|||
| E83-105 (#40) - E83-45 (E01) | L - W-B | No. 4 fuel injector assembly signal | Ignition switch ON | 11 to 14 V |
| Idling | Pulse generation (See waveform 4) |
|||
| E83-110 (KNK1) - E83-111 (EKNK) | R - G | Knock control sensor signal | Engine speed maintained at 4000 rpm after warming up engine | Pulse generation (See waveform 5) |
| E83-122 (NE+) - E83-121 (NE-) | B - W | Crankshaft position sensor signal | Idling | Pulse generation (See waveform 6) |
| E83-99 (G2+) - E83-98 (G2-) | Y - L | Camshaft position sensor signal | Idling | Pulse generation (See waveform 6) |
| E83-85 (IGT1) - E83-104 (E1) | W - BR | No. 1 ignition coil assembly (ignition signal) | Idling | Pulse generation (See waveform 7) |
| E83-84 (IGT2) - E83-104 (E1) | G - BR | No. 2 ignition coil assembly (ignition signal) | Idling | Pulse generation (See waveform 7) |
| E83-83 (IGT3) - E83-104 (E1) | GR - BR | No. 3 ignition coil assembly (ignition signal) | Idling | Pulse generation (See waveform 7) |
| E83-82 (IGT4) - E83-104 (E1) | LG - BR | No. 4 ignition coil assembly (ignition signal) | Idling | Pulse generation (See waveform 7) |
| E83-81 (IGF1) - E83-104 (E1) | V - BR | Ignition coil assembly (ignition confirmation signal) | Ignition switch ON | 4.5 to 5.5 V |
| Idling | Pulse generation (See waveform 7) |
|||
| E83-49 (PRG) - E83-45 (E01) | W - W-B | Purge VSV operation signal | Ignition switch ON | 11 to 14 V |
| Idling, under purge control | Pulse generation (See waveform 8) |
|||
| A74-8 (SPD) - E83-104 (E1) | L - BR | Vehicle speed signal from combination meter assembly | Driving at 20 km/h (12 mph) | Pulse generation (See waveform 9) |
| A74-48 (STA) - E83-104 (E1) | LG - BR | ST relay operation signal | Cranking | 5.5 V or higher |
| E83-52 (NSW) - E83-104 (E1) | LG - BR | Park/Neutral position switch assembly signal | Ignition switch ON, shift lever not in P or N | 11 to 14 V |
| Ignition switch ON, shift lever in P or N | Below 2.0 V | |||
| A74-36 (STP) - E83-104 (E1) | BE - BR | Stop light switch assembly signal | Brake pedal depressed | 7.5 to 14 V |
| Brake pedal released | Below 1.5 V | |||
| A74-35 (ST1-) - E83-104 (E1) | GR - BR | Stop light switch assembly signal (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 | |||
| E83-42 (M+) - E83-43 (ME01) | W - W-B | Throttle actuator operation signal (positive terminal) | Idling with warm engine | Pulse generation (See waveform 10) |
| E83-41 (M-) - E83-43 (ME01) | B - W-B | Throttle actuator operation signal (negative terminal) | Idling with warm engine | Pulse generation (See waveform 11) |
| A74-7 (FC) - E83-45 (E01) | V - W-B | Fuel pump control | Ignition switch ON | 11 to 14 V |
| A74-24 (W) - E83-104 (E1) | R - BR | Malfunction Indicator Lamp (MIL) operation signal | Ignition switch ON (MIL goes on) |
Below 3.0 V |
| Idling | 11 to 14 V | |||
| A74-27 (TC) - E83-104 (E1) | P - BR | Terminal TC of DLC3 | Ignition switch ON | 11 to 14 V |
| A74-15 (TACH) - E83-104 (E1) | B - BR | Engine speed signal from combination meter assembly | Idling | Pulse generation (See waveform 12) |
| E83-50 (ALT) - E83-104 (E1) | L - BR | Generator assembly | Ignition switch ON | 11 to 14 V |
| A74-41 (CANH) - E83-104 (E1) | B - BR | CAN communication line | Ignition switch ON | Pulse generation (See waveform 13) |
| A74-49 (CANL) - E83-104 (E1) | W - BR | CAN communication line | Ignition switch ON | Pulse generation (See waveform 14) |
| A74-21 (FANL) - E83-45 (E01) | R - W-B | Cooling fan motor operation signal (low) | Ignition switch ON | 11 to 14 V |
| Idling with A/C on, or high engine coolant temperature | Below 1.5 V | |||
| A74-22 (FANH) - E83-45 (E01) | W - W-B | Cooling fan motor operation signal (high) | Ignition switch ON | 11 to 14 V |
| Idling with high engine coolant temperature | Below 1.5 V | |||
| A74-32 (EC) - Body ground | W-B - - | Earth (ground) circuit of ECM | Always | Below 1 Ω |
| E83-104 (E1) - Body ground | BR - - | Earth (ground) circuit of ECM | Always | Below 1 Ω |
| E83-45 (E01) - Body ground | W-B - - | Earth (ground) circuit of ECM | Always | Below 1 Ω |
| E83-44 (E02) - Body ground | W-B - - | Earth (ground) circuit of ECM | Always | Below 1 Ω |
| E83-86 (E03) - Body ground | W-B - - | Earth (ground) circuit of ECM | Always | Below 1 Ω |
| E83-46 (E04) - Body ground | W-B - - | Earth (ground) circuit of ECM | Always | Below 1 Ω |
| E83-43 (ME01) - Body ground | W-B - - | Earth (ground) circuit of ECM | Always | Below 1 Ω |
| E83-63 (GE01) - Body ground | G - - | Shielded earth (ground) circuit of throttle actuator | Always | Below 1 Ω |
-
*1: The ECM terminal voltage is constant regardless of the output voltage from the sensor.
-
WAVEFORM 1
Camshaft Timing Oil Control Valve Assembly Operation Signal ECM Terminal Name Between OC1+ and OC1- Tester Range 5 V/DIV., 1 ms./DIV. Condition Idling -
WAVEFORM 2
Air Fuel Ratio Sensor (Sensor 1) Heater Operation Signal ECM Terminal Name Between HA1A and E04 Tester Range 5 V/DIV., 10 ms./DIV. Condition Idling Tech Tips
The wavelength varies in accordance with the engine operating condition.
-
WAVEFORM 3
Heated Oxygen Sensor (Sensor 2) Operation Signal ECM Terminal Name Between OX1B and EX1B Tester Range 0.2 V/DIV., 200 ms./DIV. Condition Engine speed maintained at 2500 rpm for 2 minutes after warming up engine Tech Tips
In the Data List, the item O2S B1S2 shows the values input to the ECM from the heated oxygen sensor.
-
WAVEFORM 4
No. 1 (to No. 4) Fuel Injector Assembly Signal ECM Terminal Name Between #10 (to #40) and E01 Tester Range 20 V/DIV., 20 ms./DIV. Condition Idling Tech Tips
The wavelength becomes shorter as the engine speed increases.
-
WAVEFORM 5
Knock Control Sensor Signal ECM Terminal Name Between KNK1 and EKNK Tester Range 1 V/DIV., 1 ms./DIV. Condition Engine speed maintained at 4000 rpm after warming up engine Tech Tips
-
The wavelength becomes shorter as the engine speed increases.
-
The waveforms and amplitudes displayed differ slightly depending on the vehicle condition.
-
-
WAVEFORM 6
Crankshaft Position Sensor Signal and Camshaft Position Sensor Signal ECM Terminal Name CH1: Between G2+ and G2-
CH2: Between NE+ and NE-
Tester Range 5 V/DIV., 20 ms./DIV. Condition Idling Tech Tips
The wavelength becomes shorter as the engine speed increases.
-
WAVEFORM 7
Ignition Coil Assembly Signal (IGT and IGF Signal) ECM Terminal Name CH1: Between IGT (1 to 4) and E1
CH2: Between IGF1 and E1
Tester Range 2 V/DIV., 20 ms./DIV. Condition Idling Tech Tips
The wavelength becomes shorter as the engine speed increases.
-
WAVEFORM 8
Purge VSV Operation Signal ECM Terminal Name Between PRG and E01 Tester Range 10 V/DIV., 20 ms./DIV. Condition Idling, under purge control Tech Tips
If the waveform is not similar to the illustration, check the waveform again after idling for 10 minutes or more.
-
WAVEFORM 9
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) Tech Tips
The wavelength becomes shorter as the vehicle speed increases.
-
WAVEFORM 10
Throttle Actuator Positive Terminal Signal ECM Terminal Name Between M+ and ME01 Tester Range 5 V/DIV., 1 ms./DIV. Condition Idling with warm engine Tech Tips
The duty ratio varies depending on the throttle actuator operation.
-
WAVEFORM 11
Throttle Actuator Negative Terminal Signal ECM Terminal Name Between M- and ME01 Tester Range 5 V/DIV., 1 ms./DIV. Condition Idling with warm engine Tech Tips
The duty ratio varies depending on the throttle actuator operation.
-
WAVEFORM 12
Engine Speed Signal ECM Terminal Name Between TACH and E1 Tester Range 5 V/DIV., 10 ms./DIV. Condition Idling Tech Tips
The wavelength becomes shorter as the engine speed increases.
-
WAVEFORM 13
CAN Communication Signal (Reference) ECM Terminal Name Between CANH and E1 Tester Range 1 V/DIV., 10 μs./DIV. Condition Ignition switch ON Tech Tips
The waveform varies depending on the CAN communication signal.
-
WAVEFORM 14
CAN Communication Signal (Reference) ECM Terminal Name Between CANL and E1 Tester Range 1 V/DIV., 10 μs./DIV. Condition Ignition switch ON Tech Tips
The waveform varies depending on the CAN communication signal.