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Electrical Specification

Fig 1: Engine Control Module I/O Signal Connector Terminals
G10292539Courtesy of SUBARU OF AMERICA, INC.
Description Connector No. Terminal No. Signal (V) Remarks
Ignition SW ON (Engine OFF) Engine ON (Idling)
Crankshaft position sensor (+) signal E158 19 0 or 5 0 or 5 Waveforms 1 and 10
Ground E158 31 0 0 -
Intake camshaft position sensor RH E158 20 0 or 5 0 or 5 Waveform 1
Intake camshaft position sensor LH E158 21 0 or 5 0 or 5 Waveform 1
Exhaust camshaft position sensor RH E158 32 0 or 5 0 or 5 Waveform 1
Exhaust camshaft position sensor LH E158 33 0 or 5 0 or 5 Waveform 1
Camshaft position sensor ground E158 34 0 0 -
Front oxygen (A/F) sensor IP (+) signal E158 15 2 - 3 2 - 4 Waveform 2
VS (+) signal E158 27 2 - 3 3 - 5 Waveform 2
COM signal E158 39 2 - 3 3 - 4 -
Heater signal E159 9 Battery voltage 0 or battery voltage Waveform 4
Rear oxygen sensor (+) signal E158 16 2 - 3 2 - 3 Waveform 3
(-) signal E158 42 2 - 3 2 - 3 -
Heater signal E159 3 Battery voltage 0 or battery voltage Waveform 4
Air flow sensor Signal B134 16 0 1 -
Ground B134 28 0 0 -
Intake air temperature sensor (integrated with air flow sensor) E158 5 2 - 3 2 - 3 -
Engine coolant temperature sensor E158 38 1 - 3 1 - 3 -
Engine oil temperature sensor E158 2 1 - 3 1 - 3 -
Manifold absolute pressure sensor E158 4 2 1 -
Intake air temperature sensor (integrated with manifold absolute pressure sensor) E158 25 2 - 3 2 - 3 -
Fuel pressure sensor E158 6 1 1 -
Knock sensor 1 E158 14 2.5 2.5 -
Knock sensor 2 E158 26 2.5 2.5 -
Accelerator pedal position sensor Main power supply B134 30 5 5 -
Main signal B134 17 Fully closed: 0.4 - 1
Fully opened: 2.4 - 3.7		 Fully closed: 0.4 - 1
Fully opened: 2.4 - 3.7		 Waveforms 2, 3, 5 and 6
Main ground B134 31 0 0 -
Sub signal B134 29 Fully closed: 0.4 - 1
Fully opened: 2.4 - 3.7		 Fully closed: 0.4 - 1
Fully opened: 2.4 - 3.7		 -
Tumble generator valve actuator RH Position signal E158 40 1 1 Fully closed: 1
Fully opened: 3
Waveform 5
Motor open E159 14 0 0 When in operation: Waveform
Waveform 5
Motor closed E159 30 0 0 When in operation: Waveform
Waveform 5
Tumble generator valve actuator LH Position signal E158 41 3 3 Fully closed: 3
Fully opened: 1
Waveform 6
Motor open E159 6 0 0 When in operation: Waveform
Waveform 6
Motor closed E159 22 0 0 When in operation: Waveform
Waveform 6
Intake oil control solenoid RH E159 7 Battery voltage 0 or battery voltage Drive frequency: 300 Hz
Waveform 7
Intake oil control solenoid LH E159 15 Battery voltage 0 or battery voltage Drive frequency: 300 Hz
Waveform 7
Exhaust oil control solenoid RH E159 23 Battery voltage 0 or battery voltage Drive frequency: 300 Hz
Waveform 7
Exhaust oil control solenoid LH E159 31 Battery voltage 0 or battery voltage Drive frequency: 300 Hz
Waveform 7
Wastegate control solenoid valve E159 11 Battery voltage Battery voltage When in operation: 0 or battery voltage
Canister purge control solenoid valve 1 E159 4 Battery voltage Battery voltage When in operation: 0 or battery voltage
Waveform 9
Canister purge control solenoid valve 2 E159 12 Battery voltage Battery voltage When in operation: 0 or battery voltage
Waveform 9
Ignition control #1 E159 8 0 0 or 5 Waveform 10
#2 E159 16 0 0 or 5 Waveform 10
#3 E159 24 0 0 or 5 Waveform 10
#4 E159 32 0 0 or 5 Waveform 10
EGR control valve A (+) E159 5 0 or battery voltage 0 or battery voltage -
A (-) E159 21 0 or battery voltage 0 or battery voltage -
B (+) E159 13 0 or battery voltage 0 or battery voltage -
B (-) E159 29 0 or battery voltage 0 or battery voltage -
Fuel pump control unit Control signal B134 40 ON: 0 or battery voltage
OFF: 0		 0 or battery voltage Waveform 8
Diagnostic signal B134 44 ON: Battery voltage
OFF: 0		 Battery voltage -
High-pressure fuel pump (Hi) E158 10 - - Measurement prohibited
High-pressure fuel pump (Lo) E158 22 - - Measurement prohibited
Fuel injector Power supply 1 B134 36 Battery voltage Battery voltage -
Power supply 2 B134 48 Battery voltage Battery voltage -
#1 (+) E158 11 0 - Measurement is prohibited while the engine is running.
#1 (-) E158 12 0 -
#2 (+) E158 23 0 -
#2 (-) E158 24 0 -
#3 (+) E158 35 0 -
#3 (-) E158 36 0 -
#4 (+) E158 47 0 -
#4 (-) E158 48 0 -
Electronic throttle control Sensor power supply E158 18 5 5 -
Main signal E158 17 Fully closed: Approx. 0.7
Fully open: Approx. 3.9		 Fully closed: Approx. 0.7
Fully open: Approx. 3.9		 -
Sub signal E158 29 Fully closed: Approx. 4.4
Fully open: Approx. 1.1		 Fully closed: Approx. 4.4
Fully open: Approx. 1.1		 -
Ground E158 30 0 0 -
Motor power supply B134 11 Battery voltage Battery voltage -
Electronic throttle control motor (+) E159 2 0 Duty waveform Drive frequency: 10 kHz
Electronic throttle control motor (-) E159 1 0 Duty waveform Drive frequency: 10 kHz
Electronic throttle relay control B134 39 0 Duty waveform -
Starter relay control B134 14 Model with push button start: 3
Models without push button start: 0		 3 Cranking: Waveforms 11 and 12
Self-shutoff relay control B134 38 1 1 -
Starter cut relay control B134 13 Model with push button start: 0
Models without push button start: 3		 Model with push button start: 0
Models without push button start: 3		 Cranking: Waveform 11
Main fan relay control B134 37 Battery voltage Battery voltage When in operation: 0 or battery voltage
Sub fan relay control B134 25 Battery voltage Battery voltage When in operation: 0 or battery voltage
A/C relay control B134 1 Battery voltage Battery voltage When in operation: 0 or battery voltage
A/C switch B134 21 ON: Battery voltage
OFF: 0		 ON: Battery voltage
OFF: 0		 Manual A/C model
Blower fan switch B134 22 ON: 0
OFF: Battery voltage		 ON: 0
OFF: Battery voltage		 Manual A/C model
Starter switch B134 45 0 0 Model with push button start
Cranking: Waveform 11
Starter switch 2 B134 8 0 0 Cranking: Battery voltage
Ignition switch B134 32 Battery voltage Battery voltage -
Pressure switch B134 7 Battery voltage Battery voltage -
Neutral position switch B134 33 ON: 0
OFF: Battery voltage		 ON: 0
OFF: Battery voltage		 Switch is ON when select lever is in "P" range or "N" range.
Cruise control Main switch B134 20 ON: 0
OFF: 5		 ON: 0
OFF: 5		 -
Command switch B134 6 When operating nothing: 3.5 - 4.5
When operating RES/+: 2.5 - 3.5
When operating SET/-: 0.5 - 1.5
When operating CANCEL: 0 - 0.5		 When operating nothing: 3.5 - 4.5
When operating RES/+: 2.5 - 3.5
When operating SET/-: 0.5 - 1.5
When operating CANCEL: 0 - 0.5		 -
Clutch switch B134 34 When clutch pedal is depressed: 0
When clutch pedal is released: Battery voltage		 When clutch pedal is depressed: 0
When clutch pedal is released: Battery voltage		 MT model
Brake switch 1 (Brake switch) B134 43 When brake pedal is depressed: 0
When brake pedal is released: Battery voltage		 When brake pedal is depressed: 0
When brake pedal is released: Battery voltage		 -
Brake switch 2 (Stop light switch) E158 8 When brake pedal is depressed: Battery voltage
When brake pedal is released: 0		 When brake pedal is depressed: Battery voltage
When brake pedal is released: 0		 -
Oil level switch E158 44 0 0 Oil level LOW: Battery voltage
Accessory cut request B134 2 Model with push button start: Battery voltage
Models without push button start: 0		 Model with push button start: Battery voltage
Models without push button start: 0		 Cranking: 0
Waveform 11
Engine speed output B134 4 Battery voltage 0 or battery voltage Waveform 12
Generator control B134 26 0 or 6.4 0 or 6.4 -
CAN communication (Hi) B134 10 - - -
(Lo) B134 9 - - -
LIN communication E158 3 - - -
Blow-by leak diagnosis E158 7 0 0 At the time of open circuit (fault): 5
Immobilizer communication E158 43 - - -
Delivery mode switch E158 45 Battery voltage Battery voltage When the fuse is installed: 0
Control module power supply B134 12 Battery voltage Battery voltage -
B134 24 Battery voltage Battery voltage -
Back-up power supply B134 23 Battery voltage Battery voltage -
Sensor power supply B134 18 5 5 -
E159 19 5 5 -
Leak check valve assembly Switching valve B134 27 Battery voltage Battery voltage Operating: 0
Pressure sensor B134 15 1 - 4 1 - 4 When ignition switch is turned to ON: atmospheric pressure
Vacuum pump B134 3 Battery voltage Battery voltage Operating: 0
Brake booster pressure sensor E158 13 1 - 2 1 - 2 When brake pedal is released.
Brake vacuum pump E158 1 0 0 -
Brake vacuum pump relay E158 37 Battery voltage Battery voltage -
Sensor ground B134 19 0 0 -
E159 27 0 0 -
Ground Engine 1 B134 35 0 0 -
Engine 2 B134 47 0 0 -
Engine 3 E159 10 0 0 -
Engine 4 E159 18 0 0 -
Engine 5 E159 26 0 0 -
Engine 6 E159 17 0 0 -
Engine 7 E159 25 0 0 -

Measuring condition: 

NOTE:
  • Perform measurement after warming up the engine.
  • For measurement of the waveform of the crankshaft position sensor, we recommend using the DST-i oscilloscope function or a general oscilloscope.
  • Place the select lever in "P" range or "N" range.
  • Turn the A/C to OFF.
  • Turn all the accessory switches to OFF.
  • Waveforms vary depending on a measurement environment and vehicle condition.
  1. Waveform 1
    Fig 2: Engine Control Module I/O Signal Waveform 1
    G11577009Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Crankshaft position sensor (+) signal (E158) No. 19 (+) - Engine ground 3 (E159) No. 10 (-):
    Intake camshaft position sensor RH (E158) No. 20 (+) - Engine ground 3 (E159) No. 10 (-):
    Intake camshaft position sensor LH (E158) No. 21 (+) - Engine ground 3 (E159) No. 10 (-):
    Exhaust camshaft position sensor RH (E158) No. 32 (+) - Engine ground 3 (E159) No. 10 (-):
    Exhaust camshaft position sensor LH (E158) No. 33 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition While engine idling
  2. Waveform 2
    Fig 3: Engine Control Module I/O Signal Waveform 2
    G11134223Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Front oxygen (A/F) sensor IP+ signal (E158) No. 15 (+) - Engine ground 3 (E159) No. 10 (-):
    Front oxygen (A/F) sensor VS+ signal (E158) No. 27 (+) - Engine ground 3 (E159) No. 10 (-):
    Accelerator pedal position sensor main signal (B134) No. 17 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition (a) Accelerator pedal fully closed (b) Accelerator pedal half open (c) Accelerator pedal fully opened
  3. Waveform 3
    Fig 4: Engine Control Module I/O Signal Waveform 3
    G11134224Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Rear oxygen sensor (E158) No. 16 (+) - (E158) No. 42 (-):
    Accelerator pedal position sensor main signal (B134) No. 17 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition (a) Accelerator pedal fully closed (b) Accelerator pedal fully opened
  4. Waveform 4
    Fig 5: Engine Control Module I/O Signal Waveform 4
    G11577011Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Front oxygen (A/F) sensor heater (E159) No. 9 (+) - Engine ground 3 (E159) No. 10 (-):
    Rear oxygen sensor heater (E159) No. 3 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition While engine idling
  5. Waveform 5
    Fig 6: Engine Control Module I/O Signal Waveform 5
    G11577012Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Tumble generator valve RH motor open (E159) No. 14 (+) - Engine ground 3 (E159) No. 10 (-):
    Tumble generator valve RH motor closed (E159) No. 30 (+) - Engine ground 3 (E159) No. 10 (-):
    Tumble generator valve RH position signal (E158) No. 40 (+) - Engine ground 3 (E159) No. 10 (-):
    Accelerator pedal position sensor main signal (B134) No. 17 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition (a) Accelerator pedal fully closed (b) Accelerator pedal fully opened
  6. Waveform 6
    Fig 7: Engine Control Module I/O Signal Waveform 6
    G11577013Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Tumble generator valve LH motor open (E159) No. 6 (+) - Engine ground 3 (E159) No. 10 (-):
    Tumble generator valve LH motor closed (E159) No. 22 (+) - Engine ground 3 (E159) No. 10 (-):
    Tumble generator valve LH position signal (E158) No. 41 (+) - Engine ground 3 (E159) No. 10 (-):
    Accelerator pedal position sensor main signal (B134) No. 17 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition (a) Accelerator pedal fully closed (b) Accelerator pedal fully opened
  7. Waveform 7
    Fig 8: Engine Control Module I/O Signal Waveform 7
    G11577014Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Intake oil control solenoid RH (E159) No. 7 (+) - Engine ground 3 (E159) No. 10 (-):
    Intake oil control solenoid LH (E159) No. 15 (+) - Engine ground 3 (E159) No. 10 (-):
    Exhaust oil control solenoid RH (E159) No. 23 (+) - Engine ground 3 (E159) No. 10 (-):
    Exhaust oil control solenoid LH (E159) No. 31 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition While engine idling
  8. Waveform 8
    Fig 9: Engine Control Module I/O Signal Waveform 8
    G11577015Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Fuel pump control unit (control signal) (B134) No. 40 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition While engine idling
  9. Waveform 9
    Fig 10: Engine Control Module I/O Signal Waveform 9
    G11577016Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Canister purge control solenoid valve 1 (E159) No. 4 (+) - Engine ground 3 (E159) No. 10 (-):
    Canister purge control solenoid valve 2 (E159) No. 12 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition Set the following items for active test to ON.
    • CPC solenoid (canister purge control solenoid valve 1)
    • CPC solenoid 2 (canister purge control solenoid valve 2)
  10. Waveform 10
    Fig 11: Engine Control Module I/O Signal Waveform 10
    G11577017Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Crankshaft position sensor (+) signal (E158) No. 19 (+) - Engine ground 3 (E159) No. 10 (-):
    Ignition control #1 (E159) No. 8 (+) - Engine ground 3 (E159) No. 10 (-):
    Ignition control #2 (E159) No. 16 (+) - Engine ground 3 (E159) No. 10 (-):
    Ignition control #3 (E159) No. 24 (+) - Engine ground 3 (E159) No. 10 (-):
    Ignition control #4 (E159) No. 32 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition While engine idling
  11. Waveform 11
    Fig 12: Engine Control Module I/O Signal Waveform 11
    G11577018Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Starter switch (B134) No. 45 (+) - Engine ground 3 (E159) No. 10 (-):
    Accessory cut request (B134) No. 2 (+) - Engine ground 3 (E159) No. 10 (-):
    Starter cut relay control (B134) No. 13 (+) - Engine ground 3 (E159) No. 10 (-):
    Starter relay control (B134) No. 14 (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition When engine is started
  12. Waveform 12
    Fig 13: Engine Control Module I/O Signal Waveform 12
    G11577019Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Starter relay control (B134) No. 14 (+) - Engine ground 3 (E159) No. 10 (-):
    Engine speed output (B134) No. 4 (+) - Engine ground 3 (E159) No. 10 (-):
    Battery voltage (battery terminal) (+) - Engine ground 3 (E159) No. 10 (-):
    Measuring condition When engine is started
    Fig 14: Accelerator Pedal Position Sensor Circuit Diagram (1 Of 4)
    G11577020Courtesy of SUBARU OF AMERICA, INC.
    Fig 15: Accelerator Pedal Position Sensor Circuit Diagram (2 Of 4)
    G11577021Courtesy of SUBARU OF AMERICA, INC.
    Fig 16: Accelerator Pedal Position Sensor Circuit Diagram (3 Of 4)
    G10267497Courtesy of SUBARU OF AMERICA, INC.
    Fig 17: Accelerator Pedal Position Sensor Circuit Diagram (4 Of 4)
    G09480867Courtesy of SUBARU OF AMERICA, INC.
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