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Electrical Specification

WARNING: This page is about a different car, the 2021 Subaru Ascent. However, it is still accessible from the selected car via links, so may be relevant.
G13866164Courtesy of SUBARU OF AMERICA, INC.
Description Connector No. Terminal No. Signal (V) Note
Ignition SW ON After warm-up (at engine OFF) Engine ON After warm-up (at idle)
Crankshaft position sensor Power supply E159 8 5 5 -
Signal E159 14 0 or 5 0 or 5 Waveforms 1 and 8
Ground E159 22 0 0 -
Intake camshaft position sensor RH E159 20 0 or 5 0 or 5 Waveform 1
LH E159 29 0 or 5 0 or 5 Waveform 1
Exhaust camshaft position sensor RH E159 21 0 or 5 0 or 5 Waveform 1
LH E159 13 0 or 5 0 or 5 Waveform 1
Camshaft position sensor ground E159 30 0 0 -
Front oxygen (A/F) sensor IP (+) signal E158 43 2 - 3 2 - 4 Waveform 2
VS (+) signal E158 56 2 - 3 3 - 5 Waveform 2
COM signal E158 44 2 - 3 3 - 4 -
Heater signal E158 65 Battery voltage 0 or battery voltage Waveform 4
Rear oxygen sensor (+) signal E158 31 2 - 3 2 - 3 Waveform 3
(-) signal E158 30 2 - 3 2 - 3 -
Heater signal E158 27 Battery voltage 0 or battery voltage Waveform 4
Air flow sensor Signal B134 63 0 1 Waveform 13
Ground B134 62 0 0 -
Intake air temperature sensor
(Integrated with air flow sensor)		 B134 3 2 - 3 2 - 3 -
Engine coolant temperature sensor E159 15 1 - 3 1 - 3 -
Engine oil temperature sensor E159 24 1 - 3 1 - 3 -
Manifold absolute pressure sensor E158 47 2 1 -
Intake air temperature sensor
(Integrated with manifold absolute pressure sensor)		 E158 59 2 - 3 2 - 3 -
Fuel pressure sensor Main signal E158 60 1 - 1.6 1 -
Sub signal E158 58 3 - 3.6 3 - 3.6 -
CPC pressure sensor E159 16 1 - 4 1 - 4 -
Knock sensor RH E158 42 2.5 2.5 -
Knock sensor LH E158 55 2.5 2.5 -
Accelerator pedal position sensor Main power supply B134 1 5 5 -
Main signal B134 16 Fully closed: 0.4 - 1
Fully open: 2.4 - 3.7		 Fully closed: 0.4 - 1
Fully open: 2.4 - 3.7		 Waveforms 2, 3, 5 and 6
Main ground B134 61 0 0 -
Sub power supply B134 14 5 5 -
Sub signal B134 42 Fully closed: 0.4 - 1
Fully open: 2.4 - 3.7		 Fully closed: 0.4 - 1
Fully open: 2.4 - 3.7		 -
Sub ground B134 48 0 0 -
Tumble generator valve RH Position signal E158 28 1 1 Fully closed: 1
Fully opened: 3
Waveform 5
Motor open E158 9 0 0 When in operation: Waveform 5
Motor closed E158 8 0 0 When in operation: Waveform 5
Tumble generator valve LH Position signal E158 29 1 1 Fully closed: 1
Fully opened: 3
Waveform 6
Motor open E158 11 0 0 When in operation: Waveform 6
Motor closed E158 10 0 0 When in operation: Waveform 6
Intake oil control solenoid RH E158 7 Battery voltage 0 or battery voltage Drive frequency: 125 Hz
Waveform 7
LH E158 6 Battery voltage 0 or battery voltage Drive frequency: 125 Hz
Waveform 7
Exhaust oil control solenoid RH E158 5 Battery voltage 0 or battery voltage Drive frequency: 125 Hz
Waveform 7
LH E158 4 Battery voltage 0 or battery voltage Drive frequency: 125 Hz
Waveform 7
Purge control solenoid valve E158 2 Battery voltage Battery voltage When in operation: 0 or battery voltage
Ignition control #1 E158 24 0 0 or 5 Waveform 8
#2 E158 37 0 0 or 5 Waveform 8
#3 E158 50 0 0 or 5 Waveform 8
#4 E158 63 0 0 or 5 Waveform 8
EGR control valve A (+) E158 25 0 or battery voltage 0 or battery voltage -
A (-) E158 51 0 or battery voltage 0 or battery voltage -
B (+) E158 38 0 or battery voltage 0 or battery voltage  
B (-) E158 64 0 or battery voltage 0 or battery voltage  
Leak check valve assembly Switching valve B134 5 Battery voltage Battery voltage Operating: 0
Vacuum pump B134 10 Battery voltage Battery voltage Operating: 0
Pressure sensor E159 31 1 - 4 1 - 4 When ignition switch is turned to ON: atmospheric pressure
Fuel pump control unit Control signal B134 25 ON: 0 or battery voltage
OFF: 0		 0 or battery voltage Waveform 9
Diagnostic signal B134 34 ON: Battery voltage
OFF: 0		 Battery voltage -
High-pressure fuel pump HI E159 3 - - Measurement prohibited
LO E159 4 - - Measurement prohibited
Fuel injector Power supply 1 E158 1 Battery voltage Battery voltage -
Power supply 2 E158 14 Battery voltage Battery voltage -
#1 (+) E159 2 0 - Measurement is prohibited while the engine is running.
#1 (-) E159 1 0 -
#2 (+) E159 10 0 -
#2 (-) E159 9 0 -
#3 (+) E159 18 0 -
#3 (-) E159 17 0 -
#4 (+) E159 26 0 -
#4 (-) E159 25 0 -
Electronic throttle control Power supply E158 49 5 5 -
Main signal E158 34 Fully closed: Approx. 0.7
Fully open: Approx. 3.9		 Fully closed: Approx. 0.7
Fully open: Approx. 3.9		 -
Sub signal E158 32 Fully closed: Approx. 4.4
Fully open: 1.1		 Fully closed: Approx. 4.4
Fully open: 1.1		 -
Ground E158 20 0 0 -
Motor (+) E158 13 0 0 or battery voltage Drive frequency: 10 kHz
Motor (-) E158 26 0 0 or battery voltage Drive frequency: 10 kHz
Electronic throttle control motor power supply B134 65 Battery voltage Battery voltage -
Electronic throttle control relay control B134 36 0 0 -
Electronic wastegate valve Position signal E159 23 1 - 1.4 1 - 1.4 -
Motor (+) E158 39 0 0 or battery voltage -
Motor (-) E158 52 0 0 or battery voltage -
Electronic air by-pass valve E158 12 Battery voltage Battery voltage -
Radiator main fan Control signal B134 23 0 0 ON
Diagnostic signal B134 18 Battery voltage Battery voltage -
Main fan relay control B134 12 0 0 -
Radiator sub fan Control signal B134 37 0 0 ON
Diagnostic signal B134 31 Battery voltage Battery voltage -
Sub fan relay control B134 50 0 0 -
Self-shutoff relay control B134 49 0 0 -
Starter relay control B134 9 Models without push button start: 0
Model with push button start: 3		 3 Models without push button start: Waveform 10
Models with push button start: Waveform 12
Starter cut relay control B134 8 Battery voltage Battery voltage Models without push button start: Waveform 10
Models with push button start: Waveform 11 and 12
Starter switch B134 4 0 0 Models without push button start: Waveform 10
Models with push button start: Waveform 11
Starter switch 2 B134 19 0 0 Models without push button start: Waveform 10
Models with push button start: Waveform 11
Accessory cut request B134 51 Battery voltage Battery voltage Models with push button start: Waveform 11
Engine speed output B134 24 Battery voltage 0 or battery voltage Models with push button start: Waveform 12
Brake switch 1 (Brake switch) B134 35 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) B134 20 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		 -
Neutral position switch E158 17 ON: 0
OFF: Battery voltage		 ON: 0
OFF: Battery voltage		 Switch is ON when select lever is in "P" range or "N" range.
Oil level switch E159 11 0 0 Oil level LOW: Battery voltage
Ignition switch B134 46 Battery voltage Battery voltage Models with push button start: Waveform 12
Delivery mode switch B134 21 Battery voltage Battery voltage When the fuse is installed: 0
Blow-by leak diagnosis E159 12 0 0 At the time of open circuit (fault): 5
CAN communication HI B134 45 - - -
LO B134 58 - - -
LIN communication B134 56 - - -
Immobilizer communication B134 43 - - -
Control module power supply B134 13 Battery voltage Battery voltage -
B134 26 Battery voltage Battery voltage -
Backup power supply B134 39 Battery voltage Battery voltage -
Sensor power supply B134 2 5 5 -
B134 15 5 5 -
E158 62 5 5 -
E159 7 5 5 -
Ground Body B134 64 0 0 -
Sensor E158 22 0 0 -
E159 5 0 0 -
Engine 1 B134 52 0 0 -
Engine 2 B134 27 0 0 -
Engine 3 B134 40 0 0 -
Engine 4 E158 40 0 0 -
Engine 5 E158 53 0 0 -
Engine 6 E159 19 0 0 -
Engine 7 E159 27 0 0 -
Engine 8 B134 53 0 0 -
NOTE:
  • After engine is warmed up, attach the check board for measurement.
  • 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.
  • Oscilloscope waveform illustrated here is an example for reference. Noise and chattering in waveform are omitted.
  1. Waveform 1
    G13866165Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Crankshaft position sensor signal (E159) No. 14 (+) - Engine ground 3 (B134) No. 40 (-):
    Intake camshaft position sensor RH (E159) No. 20 (+) - Engine ground 3 (B134) No. 40 (-):
    Intake camshaft position sensor LH (E159) No. 29 (+) - Engine ground 3 (B134) No. 40 (-):
    Exhaust camshaft position sensor RH (E159) No. 21 (+) - Engine ground 3 (B134) No. 40 (-):
    Exhaust camshaft position sensor LH (E159) No. 13 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition While engine idling
  2. Waveform 2
    G13866166Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Front oxygen (A/F) sensor IP (+) signal (E158) No. 43 (+) - Engine ground 3 (B134) No. 40 (-):
    Front oxygen (A/F) sensor VS (+) signal (E158) No. 56 (+) - Engine ground 3 (B134) No. 40 (-):
    Accelerator pedal position sensor main signal (B134) No. 16 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition (a) accelerator pedal fully closed (b) accelerator pedal half open (c) accelerator pedal fully opened
  3. Waveform 3
    G13866167Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Rear oxygen sensor (+) signal (E158) No. 31 (+) - Rear oxygen sensor (-) signal (E158) No. 30 (-):
    Accelerator pedal position sensor main signal (B134) No. 16 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition (a) Accelerator pedal fully closed (b) Accelerator pedal fully opened
  4. Waveform 4
    G13866168Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Front oxygen (A/F) sensor heater signal (E158) No. 65 (+) - Engine ground 3 (B134) No. 40 (-):
    Rear oxygen sensor heater signal (E158) No. 27 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition While engine idling
  5. Waveform 5
    G13866169Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Tumble generator valve RH position signal (E158) No. 28 (+) - Engine ground 3 (B134) No. 40 (-):
    Tumble generator valve RH motor open (E158) No. 9 (+) - Engine ground 3 (B134) No. 40 (-):
    Tumble generator valve RH motor closed (E158) No. 8 (+) - Engine ground 3 (B134) No. 40 (-):
    Accelerator pedal position sensor main signal (B134) No. 16 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition (a) Accelerator pedal fully closed (b) Accelerator pedal fully opened
  6. Waveform 6
    G13866170Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Tumble generator valve LH position signal (E158) No. 29 (+) - Engine ground 3 (B134) No. 40 (-):
    Tumble generator valve LH motor open (E158) No. 11 (+) - Engine ground 3 (B134) No. 40 (-):
    Tumble generator valve LH motor closed (E158) No. 10 (+) - Engine ground 3 (B134) No. 40 (-):
    Accelerator pedal position sensor main signal (B134) No. 16 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition (a) Accelerator pedal fully closed (b) Accelerator pedal fully opened
  7. Waveform 7
    G13866171Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Intake oil control solenoid RH (E158) No. 7 (+) - Engine ground 3 (B134) No. 40 (-):
    Intake oil control solenoid LH (E158) No. 6 (+) - Engine ground 3 (B134) No. 40 (-):
    Exhaust oil control solenoid RH (E158) No. 5 (+) - Engine ground 3 (B134) No. 40 (-):
    Exhaust oil control solenoid LH (E158) No. 4 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition While engine idling
  8. Waveform 8
    G13866172Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Crankshaft position sensor signal (E159) No. 14 (+) - Engine ground 3 (B134) No. 40 (-):
    Ignition control #1 (E158) No. 24 (+) - Engine ground 3 (B134) No. 40 (-):
    Ignition control #2 (E158) No. 37 (+) - Engine ground 3 (B134) No. 40 (-):
    Ignition control #3 (E158) No. 50 (+) - Engine ground 3 (B134) No. 40 (-):
    Ignition control #4 (E158) No. 63 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition While engine idling
  9. Waveform 9
    G13866173Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Fuel pump control (B134) No. 25 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition While engine idling
  10. Waveform 10
    G13866174Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Starter switch (B134) No. 4 (+) - Engine ground 3 (B134) No. 40 (-):
    Starter switch 2 (B134) No. 19 (+) - Engine ground 3 (B134) No. 40 (-):
    Starter cut relay control (B134) No. 8 (+) - Engine ground 3 (B134) No. 40 (-):
    Starter relay control (B134) No. 9 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition When engine is started
  11. Waveform 11
    G13866175Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Starter switch (B134) No. 4 (+) - Engine ground 3 (B134) No. 40 (-):
    Starter switch 2 (B134) No. 19 (+) - Engine ground 3 (B134) No. 40 (-):
    Starter cut relay control (B134) No. 8 (+) - Engine ground 3 (B134) No. 40 (-):
    Accessory cut request (B134) No. 51 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition When engine is started
  12. Waveform 12
    G13866176Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Starter cut relay control (B134) No. 8 (+) - Engine ground 3 (B134) No. 40 (-):
    Starter relay control (B134) No. 9 (+) - Engine ground 3 (B134) No. 40 (-):
    Engine speed output (B134) No. 24 (+) - Engine ground 3 (B134) No. 40 (-):
    Ignition switch (B134) No. 46 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition When engine is started
  13. Waveform 13
    G13866177Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Air flow sensor signal (B134) No. 63 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition While engine idling
    G13866178Courtesy of SUBARU OF AMERICA, INC.
    G13866179Courtesy of SUBARU OF AMERICA, INC.
    G13866180Courtesy of SUBARU OF AMERICA, INC.
    G13866181Courtesy of SUBARU OF AMERICA, INC.
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