2020 Subaru Ascent BaseFACTORY OEM SERVICE PROCEDURE

Electrical Specification

G13202298Courtesy 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 -
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 1 E158 42 2.5 2.5 -
Knock sensor 2 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 Operation frequency: 125 Hz Waveform 7
LH E158 6 Battery voltage 0 or battery voltage Operation frequency: 125 Hz Waveform 7
Exhaust oil control solenoid RH E158 5 Battery voltage 0 or battery voltage Operation frequency: 125 Hz Waveform 7
LH E158 4 Battery voltage 0 or battery voltage Operation 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 Operation frequency: 10 kHz
Motor (-) E158 26 0 0 or battery voltage Operation 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 Model with push button start
Starter cut relay control B134 8 Battery voltage Battery voltage Models without push button start: Waveform 10 Model with push button start
Starter switch B134 4 0 0 Models without push button start: Waveform 10 Model with push button start
Starter switch 2 B134 19 0 0 Models without push button start: Waveform 10 Model with push button start
Accessory cut request B134 51 Battery voltage Battery voltage Model with push button start
Engine speed output B134 24 Battery voltage 0 or battery voltage Model with push button start
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 -
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
    G13202299Courtesy 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
    G13202300Courtesy 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
    G13202301Courtesy 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
    G13202302Courtesy 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
    G13202303Courtesy 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
    G13202304Courtesy 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
    G13202305Courtesy 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
    G13202306Courtesy 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
    G13202307Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Fuel pump control (B134) No. 25 (+) - Engine ground 3 (B134) No. 40 (-):
    Measuring condition When engine is started
  10. Waveform 10 (Model without push button start)
    G13202308Courtesy 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
G13202309Courtesy of SUBARU OF AMERICA, INC.
G13202310Courtesy of SUBARU OF AMERICA, INC.
G13202311Courtesy of SUBARU OF AMERICA, INC.
G13202312Courtesy of SUBARU OF AMERICA, INC.
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