Tech Tips
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 STD Voltages column. The illustration above can be used as a reference to identify the ECM terminal locations.
| Terminal No. (Symbols) | Wiring Colors | Terminal Descriptions | Conditions | STD Voltages |
|---|---|---|---|---|
| B71-20 (BATT) - D97-105 (E1) | W - W-B | Battery (for measuring the battery voltage and for the ECM memory) | Always | 11 to 14 V |
| B71-3 (+BM) - D97-105 (E1) | Y - W-B | Power source of throttle actuator | Always | 11 to 14 V |
| B71-27 (IGSW) - D97-105 (E1) | B - W-B | Ignition switch | Ignition switch ON | 11 to 14 V |
| B71-2 (+B) - D97-105 (E1) | L - W-B | Power source of ECM | Ignition switch ON | 11 to 14 V |
| B71-44 (MREL) - D97-105 (E1) | G - W-B | EFI relay | Ignition switch ON | 11 to 14 V |
| D97-119 (VC) - D97-72 (E2) | L - Y | Power source of sensor (specific voltage) |
Ignition switch ON | 4.5 to 5.0 V |
| D97-113 (VTA1) - D97-72 (E2) | R - Y | Throttle position sensor (for engine control) |
Ignition switch ON, Accelerator pedal fully released | 0.5 to 1.1 V |
| Ignition switch ON, Accelerator pedal fully depressed | 3.3 to 4.9 V | |||
| D97-112 (VTA2) - D97-72 (E2) | G - Y | Throttle position sensor (for sensor malfunction detection) |
Ignition switch ON, Accelerator pedal fully released | 2.1 to 3.1 V |
| Ignition switch ON, Accelerator pedal fully depressed | 4.5 to 5.0 V | |||
| B71-55 (VPA) - B71-59 (EPA) | L - G | Accelerator pedal position sensor (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 | |||
| B71-56 (VPA2) - B71-60 (EPA2) | B - GR | Accelerator pedal position sensor (for sensor malfunction detection) |
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 | |||
| B71-57 (VCPA) - B71-59 (EPA) | W - G | Power source of accelerator pedal position sensor (for VPA) |
Ignition switch ON | 4.5 to 5.5 V |
| B71-58 (VCP2) - B71-60 (EPA2) | R - GR | Power source of accelerator pedal position sensor (for VPA2) |
Ignition switch ON | 4.5 to 5.5 V |
| D97-69 (VG) - D97-92 (E2G) | Y-G - L | Mass air flow meter | Idling, Shift lever in neutral, A/C switch OFF | 0.5 to 3.0 V |
| D97-87 (THA) - D97-72 (E2) | R - Y | Intake air temperature sensor | Idling, Intake air temperature 20°C (68°F) | 0.5 to 3.4 V |
| D97-64 (THW) - D97-72 (E2) | R-W - Y | Engine coolant temperature sensor | Idling, Engine coolant temperature 80°C (176°F) | 0.2 to 1.0 V |
| D97-66 (RTHW) - D97-72 (E2) | L - Y | Engine coolant temperature (radiator) sensor | Idling, radiator side engine coolant temperature -20 to 80°C (-4 to 176°F) | 0.5 to 4.5 V |
| D97-86 (#10) - D97-46 (E01) | B - W-B | Fuel injector | Ignition switch ON | 11 to 14 V |
| D97-85 (#20) - D97-46 (E01) | L - W-B | |||
| D97-84 (#30) - D97-46 (E01) | Y - W-B | Idling | Pulse generation (see waveform 1) |
|
| D97-83 (#40) - D97-46 (E01) | R - W-B | |||
| D97-109 (IGT1) - D97-105 (E1) | R-L - W-B | Ignition coil with igniter (ignition coil signal) |
Idling | Pulse generation (see waveform 2) |
| D97-108 (IGT2) - D97-105 (E1) | L-W - W-B | |||
| D97-107 (IGT3) - D97-105 (E1) | B-Y - W-B | |||
| D97-106 (IGT4) - D97-105 (E1) | Y-R - W-B | |||
| D97-82 (IGF1) - D97-105 (E1) | W-R - W-B | Ignition coil with igniter (ignition confirmation signal) |
Ignition switch ON | 4.5 to 5.0 V |
| Idling | Pulse generation (see waveform 2) |
|||
| D97-94 (G2) - D97-118 (G2-) | Y - L | Camshaft position sensor | Idling | Pulse generation (see waveform 3) |
| D97-93 (NE+) - D97-117 (NE-) | W - B | Crankshaft position sensor | Idling | Pulse generation (see waveform 3) |
| B71-19 (FC) - D97-105 (E1) | L - W-B | Fuel pump control | Ignition switch ON | 11 to 14 V |
| Idling | Below 1.5 V | |||
| D97-43 (M+) - D97-44 (ME01) | Y - W-B | Throttle actuator | Idling with warm engine | Pulse generation (see waveform 4) |
| D97-42 (M-) - D97-44 (ME01) | L - W-B | Throttle actuator | Idling with warm engine | Pulse generation (see waveform 5) |
| D97-103 (A1A+) - D97-72 (E2) | B - Y | Heated oxygen sensor | Engine speed maintained 2500 rpm for 2 minutes after warming up sensor | Pulse generation (see waveform 6) |
| D97-104 (HA1A) - D97-81 (E03) | Y - W-B | Heated oxygen sensor heater | Idling | Below 3.0 V |
| Ignition switch ON | 11 to 14 V | |||
| D97-110 (KNK1) - D97-111 (EKNK) | G - R | Knock sensor | Maintain engine speed 4000 rpm after warming up | Pulse generation (see waveform 7) |
| D97-74 (OC1+) - D97-96 (OC1-) | G - B | Camshaft timing oil control valve (OCV) | Idling | Pulse generation (see waveform 8) |
| D97-62 (PRG) - D97-105 (E1) | B - W-B | EVAP VSV | Ignition switch ON | 11 to 14 V |
| Idling | Pulse generation (see waveform 9) |
|||
| B71-48 (STA) - D97-105 (E1) | R - W-B | Starter signal | Shift lever in neutral, ignition switch START | 5.5 V or more |
| B71-36 (STP) - D97-105 (E1) | Y - W-B | Stop light switch | Brake pedal depressed | 7.5 to 14 V |
| Brake pedal released | Below 1.5 V | |||
| B71-35 (ST1-) - D97-105 (E1) | R - W-B | Stop light switch | Ignition switch ON, Brake pedal depressed | Below 1.5 V |
| Ignition switch ON, Brake pedal released | 7.5 to 14 V | |||
| B71-31 (ELS) - D97-105 (E1) | G - W-B | Electric load | Taillight ON | 7.5 to 14 V |
| Taillight OFF | 0 to 1.5 V | |||
| B71-50 (ELS2) - D97-105 (E1) | B - W-B | Electric load | Defogger ON | 7.5 to 14 V |
| Defogger OFF | 0 to 1.5 V | |||
| B71-15 (TACH) - D97-105 (E1) | B - W-B | Engine speed | Idling | Pulse generation (see waveform 10) |
| B71-38 (SPD) - D97-105 (E1) | P - W-B | Speed signal from combination meter | Driving at 20 km/h (12 mph) | Pulse generation (see waveform 11) |
| B71-41 (TC) - D97-105 (E1) | G - W-B | Terminal TC of DLC3 | Ignition switch ON | 11 to 14 V |
| B71-52 (PSW) - D97-105 (E1) | G - W-B | Power steering oil pressure switch | While turning steering wheel | Below 1.5 V |
| B71-46 (F/PS) - D97-105 (E1) | B - W-B | Airbag sensor assembly | Idling with warm engine | Pulse generation (see waveform 12) |
| B71-8 (CANH) - D97-105 (E1) | B - W-B | Communication signal with other components | Ignition switch ON | Pulse generation (see waveform 13) |
| B71-9 (CANL) - D97-105 (E1) | W - W-B | Communication signal with other components | Ignition switch ON | Pulse generation (see waveform 14) |
| D97-80 (OX1B) - D97-72 (E2) | B - Y | Variable resistor | Ignition switch ON | 0 to 5.5 V |
*1: The ECM terminal voltage is constant regardless of the output voltage from the sensor.
WAVEFORM 1
Fuel injector
| ECM Terminal Names | Between #1 (to #4) and E01 |
| Tester Ranges | 20 V/DIV, 20 msec./DIV |
| Conditions | Idling |
Tech Tips
The wavelength becomes shorter as the engine rpm increases.
WAVEFORM 2
Igniter IGT signal (from ECM to igniter)
Igniter IGF signal (from igniter to ECM)
| ECM Terminal Names |
|
| Tester Ranges | 2 V/DIV, 20 msec./DIV |
| Conditions | Idling |
Tech Tips
The wavelength becomes shorter as the engine rpm increases.
WAVEFORM 3
Camshaft position sensor
Crankshaft position sensor
| ECM Terminal Names |
|
| Tester Ranges | 5 V/DIV, 20 msec./DIV |
| Conditions | Idling |
Tech Tips
The wavelength becomes shorter as the engine rpm increases.
WAVEFORM 4
Throttle actuator positive terminal
| ECM Terminal Names | Between M+ and ME01 |
| Tester Ranges | 5 V/DIV, 1 msec./DIV |
| Conditions | Idling with warm engine |
Tech Tips
The duty ratio varies depending on the throttle actuator operation.
WAVEFORM 5
Throttle actuator negative terminal
| ECM Terminal Names | Between M- and ME01 |
| Tester Ranges | 5 V/DIV, 1 msec./DIV |
| Conditions | Idling with warm engine |
Tech Tips
The duty ratio varies depending on the throttle actuator operation.
WAVEFORM 6
Heated oxygen sensor
| ECM Terminal Names | Between A1A+ and E2 |
| Tester Ranges | 0.2 V/DIV, 200 msec./DIV |
| Conditions | Engine speed maintained 2500 rpm for 2 minutes after warming up engine |
Tech Tips
In the DATA LIST, item O2S B1S1 shows the ECM input values from the heated oxygen sensor.
WAVEFORM 7
Knock sensor
| ECM Terminal Names | Between KNK1 and EKNK |
| Tester Ranges | 1 V/DIV, 1 msec./DIV |
| Conditions | Engine speed maintained 4000 rpm after warming up engine |
Tech Tips
The wavelength becomes shorter as the engine rpm increases.
The waveforms and amplitudes displayed differ slightly depending on the vehicle.
WAVEFORM 8
Camshaft timing oil control valve (OCV)
| ECM Terminal Names | Between OC1+ and OC1- |
| Tester Ranges | 5 V/DIV, 1 msec./DIV |
| Conditions | Idling |
Tech Tips
The wavelength becomes shorter as the engine rpm increases.
WAVEFORM 9
EVAP VSV
| ECM Terminal Names | Between PRG and E01 |
| Tester Ranges | 10 V/DIV, 20 msec./DIV |
| Conditions | Idling |
Tech Tips
If the waveform is not similar to the illustration, check the waveform again after idling for 10 minutes or more.
WAVEFORM 10
Engine speed signal
| ECM Terminal Names | Between TACH and E1 |
| Tester Ranges | 5 V/DIV, 10 msec./DIV |
| Conditions | Idling |
Tech Tips
The wavelength becomes shorter as the engine rpm increases.
WAVEFORM 11
Vehicle speed signal
| ECM Terminal Names | Between SPD and E1 |
| Tester Ranges | 5 V/DIV, 20 msec./DIV |
| Conditions | Driving at 20 km/h (12 mph) |
Tech Tips
The wavelength becomes shorter as the vehicle speed increases.
WAVEFORM 12
Airbag sensor assembly
| ECM Terminal Names | Between F/PS and E1 |
| Tester Ranges | 5 V/DIV, 500 msec./DIV |
| Conditions | Idling with warm engine |
WAVEFORM 13
CAN communication signal
| ECM Terminal Names | Between CANH and E1 |
| Tester Ranges | 1 V/DIV, 10 μs/DIV |
| Conditions | Ignition switch ON |
WAVEFORM 14
CAN communication signal
| ECM Terminal Names | Between CANL and E1 |
| Tester Ranges | 1 V/DIV, 10 μs/DIV |
| Conditions | Ignition switch ON |