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Home >> Subaru >> 2018 >> Forester 2.5i Limited >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics - Introduction) (H4DO) >> Engine Control Module (ECM) I/O Signal >> Electrical Specification
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Electrical Specification

G12519026Courtesy 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 (+) signal B135 40 1 or 5 1 or 5 Waveform 1, 8 and 9
Ground B135 27 0 0 -
Power supply B135 28 5 5 -
Intake camshaft position sensor RH B135 54 0 or 5 0 or 5 Waveform 1
LH B135 41 0 or 5 0 or 5 Waveform 1
Camshaft position sensor ground B135 42 0 0 -
Front oxygen (A/F) sensor (+) signal B135 46 2.8-3.2 2.8-3.2 Waveform 2
(-) signal B135 33 1.3-3.1 2.4-2.7 Waveform 2
Heater signal B135 5 Battery voltage 0 or battery voltage Waveform 4
Rear oxygen sensor (+) signal B135 57 0.1-0.3 0.2-2.1 Waveform 3
(-) signal B135 56 1.4-1.5 1.1-1.7 -
Heater signal B135 10 Battery voltage 0 or battery voltage Waveform 4
Oxygen sensor shield B135 58 0 0 -
Air flow sensor Signal B134 16 0.6- 1 0.3-4.5 -
Ground B134 17 0 0 -
Shield B134 3 0 0 -
Intake air temperature sensor signal B134 15 0.3-4.6 0.3-4.6 -
Engine coolant temperature sensor signal B135 43 1 -1.4 1 -1.4 -
Engine oil temperature sensor signal B135 18 1 -1.4 1 -1.4 -
Manifold absolute pressure sensor signal B135 15 3.5-4.8 1.4-2.1 -
Knock sensor Signal B135 30 2.4-2.6 2.1-2.8 -
Shield B135 17 0 0 -
Accelerator pedal position sensor Main signal B134 29 Fully closed: 0.3-1.1
Fully open: 2.3-3.8		 Fully closed: 0.3-1.4
Fully open: 2.4-3.8		 Waveforms 2, 3, 5 and 6
Main power supply B134 30 5 5 -
Main ground B134 33 0 0 -
Sub signal B134 31 Fully closed: 0.3-1.1
Fully open: 2.3-3.8		 Fully closed: 0.3-1.4
Fully open: 2.3-3.8		 -
Sub power supply B134 28 5 5 -
Sub ground B134 34 0 0 -
Tumble generator valve RH Position signal B135 47 Waveform Waveform Waveform 5
Motor open B135 52 Waveform Waveform Waveform 5
Motor closed B135 13 Waveform Waveform Waveform 5
Tumble generator valve LH Position signal B135 59 Waveform Waveform Waveform 6
Motor open B135 26 Waveform Waveform Waveform 6
Motor closed B135 39 Waveform Waveform Waveform 6
Intake oil control solenoid RH B135 20 Battery voltage 0 or battery voltage Waveform 7
LH B135 6 Battery voltage 0 or battery voltage Waveform 7
Purge control solenoid valve B135 51 Battery voltage Battery voltage When in operation: Waveform 11
Leak check valve assembly Switching valve B134 61 Battery voltage Battery voltage Operating: 0
Pressure sensor B134 21 1 - 4 1 - 4 When ignition switch is turned to ON: atmospheric pressure
Vacuum pump B134 9 Battery voltage Battery voltage Operating: 0
Ignition control #1 B135 37 0 0 or 5 Waveform 8
#2 B135 35 0 0 or 5 Waveform 8
#3 B135 38 0 0 or 5 Waveform 8
#4 B135 36 0 0 or 5 Waveform 8
Fuel injector #1 B135 23 Battery voltage 0 or battery voltage Waveform 9
#2 B135 8 Battery voltage 0 or battery voltage Waveform 9
#3 B135 9 Battery voltage 0 or battery voltage Waveform 9
#4 B135 22 Battery voltage 0 or battery voltage Waveform 9
EGR control valve Signal 1 B135 12 0 or battery voltage 0 or battery voltage -
Signal 2 B135 48 0 or battery voltage 0 or battery voltage -
Signal 3 B135 25 0 or battery voltage 0 or battery voltage -
Signal 4 B135 49 0 or battery voltage 0 or battery voltage -
Electronic throttle control Main signal B135 29 Approx. 0.7 Approx. 0.6-1.2 Fully closed: Approx. 0.6-1.2
Fully open: Approx. 3.8-4.4
Sub signal B135 31 Approx. 1.6 Approx. 1.5-1.7 Fully closed: Approx. 1.4- 2
Fully open: Approx. 4 -4.6
Shield B135 19 0 0 -
Motor (+) B135 14 0 or battery voltage 0 or battery voltage Drive frequency: 500 Hz
Motor (-) B135 1 0 or battery voltage 0 or battery voltage Drive frequency: 500 Hz
Electronic throttle control motor power supply B134 13 Battery voltage Battery voltage -
Electronic throttle relay control B134 65 ON: 0 ON: 0 -
Self-shutoff relay control B134 60 0 0 -
Starter relay control B134 62 Waveform Waveform Waveform 10 (Model without push button start)
Starter cut relay control B134 49 Waveform Waveform Model with push button start
Fuel pump relay control B134 63 Battery voltage 0 ON: 0
OFF: Battery voltage
A/C relay B134 50 Battery voltage Battery voltage ON: 0
A/C switch B134 47 ON: Battery voltage
OFF: 0		 ON: Battery voltage
OFF: 0		 Manual A/C model
Blower fan switch B134 43 ON: 0
OFF: Battery voltage		 ON: 0
OFF: Battery voltage		 Manual A/C model
Main fan relay control B134 51 Battery voltage Battery voltage ON: 0
Sub fan relay control B134 37 Battery voltage Battery voltage ON: 0
Ignition switch B134 2 Battery voltage Battery voltage -
Neutral position switch B134 5 ON: 0
OFF: Battery voltage		 ON: 0
OFF: Battery voltage		 -
Delivery mode switch B134 6 Battery voltage Battery voltage When fuse is installed: 0
Oil level switch B135 3 0 0 Oil level LOW: 10 - 14
Clutch switch B134 42 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
Starter switch B134 46 Waveform Waveform Waveform 10 (Model without push button start)
Starter switch 2 B134 58 0 0 Model with push button start
Accessory cut request B134 64 Battery voltage Battery voltage Model with push button start
Engine speed output B134 10 0 0 or battery voltage Model with push button start
A/C middle pressure switch B134 57 ON: 0
OFF: Battery voltage		 ON: 0
OFF: Battery voltage		 -
Brake switch 1
(Brake switch)		 B134 59 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 48 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		 -
Cruise control main switch B134 44 ON: 0
OFF: 5		 ON: 0
OFF: 5		 Model without EyeSight (with cruise control)
Cruise control command switch B134 22 When operating nothing: 3.5-4.5
When operating RES/ACC: 2.5-3.5
When operating SET/COAST: 0.5-1.5
When operating CANCEL: 0 -0.5		 When operating nothing: 3.5-4.5
When operating RES/ACC: 2.5-3.5
When operating SET/COAST: 0.5-1.5
When operating CANCEL: 0 -0.5		 Model without EyeSight (with cruise control)
LIN communication B134 55 - - -
Immobilizer communication B134 38 - - -
CAN communication HI B134 25 - - -
LO B134 24 - - -
Control module power supply B134 1 Battery voltage Battery voltage -
B134 14 Battery voltage Battery voltage -
Backup power supply B134 27 Battery voltage Battery voltage Ignition switch OFF: Battery voltage
Sensor power supply B134 35 5 5 -
B135 32 5 5 -
Ground Body B134 53 0 0 -
Sensor B134 32 0 0 -
B135 34 0 0 -
Engine 1 B135 65 0 0 -
Engine 2 B135 64 0 0 -
Engine 3 B135 63 0 0 -
Engine 4 B135 62 0 0 -
Engine 5 B135 61 0 0 -
NOTE:
  • After engine is warmed up, attach the check board for measurement.
  • Set the select lever in "P" range or "N" range, or the shift lever in neutral.
  • Turn the A/C to OFF.
  • Turn all the accessory switches to OFF.
  • Waveforms vary depending on a measurement environment and vehicle condition.
NOTE:
  • For measurement of the waveform of the crankshaft position sensor, we recommend using the DST-i oscilloscope function or a general oscilloscope.
  • The waveform of the crankshaft position sensor may be shown as in diagram (A) using the oscilloscope function of the Subaru Select Monitor.

    This is because the output unit of the crankshaft position sensor is smaller than the minimal measurement unit of the Subaru Select Monitor, and therefore this phenomenon is not a malfunction of either the Subaru Select monitor or the crankshaft position sensor.

G12519027Courtesy of SUBARU OF AMERICA, INC.
  1. Waveform 1
    G12519028Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Crankshaft position sensor (+) signal (B135) No. 40 (+) - Engine ground 3 (B135) No. 63 (-):
    Intake camshaft position sensor RH (B135) No. 54 (+) - Engine ground 3 (B135) No. 63 (-):
    Intake camshaft position sensor LH (B135) No. 41 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition While engine idling
  2. Waveform 2
    G12519029Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Front oxygen (A/F) sensor (+) signal (B135) No. 46 (+) - Engine ground 3 (B135) No. 63 (-):
    Front oxygen (A/F) sensor (-) signal (B135) No. 33 (+) - Engine ground 3 (B135) No. 63 (-):
    Accelerator pedal position sensor main signal (B134) No. 29 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition (A) Accelerator pedal fully closed (B) Accelerator pedal fully opened
  3. Waveform 3
    G12519030Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Rear oxygen sensor (+) signal (B135) No. 57 (+) - Rear oxygen sensor (-) signal (B135) No. 56 (-):
    Accelerator pedal position sensor main signal (B134) No. 29 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition (A) Accelerator pedal fully closed (B) Accelerator pedal fully opened
  4. Waveform 4
    G12519031Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Front oxygen (A/F) sensor heater signal (B135) No. 5 (+) - Engine ground 3 (B135) No. 63 (-):
    Rear oxygen sensor heater signal (B135) No. 10 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition While engine idling (heater driven)
  5. Waveform 5
    G12519032Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Tumble generator valve RH position signal (B135) No. 47 (+) - Engine ground 3 (B135) No. 63 (-):
    Tumble generator valve RH motor open (B135) No. 52 (+) - Engine ground 3 (B135) No. 63 (-):
    Tumble generator valve RH motor closed (B135) No. 13 (+) - Engine ground 3 (B135) No. 63 (-):
    Accelerator pedal position sensor main signal (B134) No. 29 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition (A) Accelerator pedal fully closed (B) Accelerator pedal fully opened
  6. Waveform 6
    G12519033Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Tumble generator valve LH position signal (B135) No. 59 (+) - Engine ground 3 (B135) No. 63 (-):
    Tumble generator valve LH motor open (B135) No. 26 (+) - Engine ground 3 (B135) No. 63 (-):
    Tumble generator valve LH motor closed (E135) No. 39 (+) - Engine ground 3 (B135) No. 63 (-):
    Accelerator pedal position sensor main signal (B134) No. 29 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition (a) Accelerator pedal fully closed (b) Accelerator pedal fully opened
  7. Waveform 7
    G12519034Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Intake oil control solenoid RH (B135) No. 20 (+) - Engine ground 3 (B135) No. 63 (-):
    Intake oil control solenoid LH (B135) No. 6 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition While engine idling
  8. Waveform 8
    G12519035Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Crankshaft position sensor (+) signal (B135) No. 40 (+) - Engine ground 3 (B135) No. 63 (-):
    Ignition control #1 (B135) No. 37 (+) - Engine ground 3 (B135) No. 63 (-):
    Ignition control #2 (B135) No. 35 (+) - Engine ground 3 (B135) No. 63 (-):
    Ignition control #3 (B135) No. 38 (+) - Engine ground 3 (B135) No. 63 (-):
    Ignition control #4 (B135) No. 36 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition While engine idling
  9. Waveform 9
    G12519036Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Crankshaft position sensor (+) signal (B135) No. 40 (+) - Engine ground 3 (B135) No. 63 (-):
    Fuel injector #1 (B135) No. 23 (+) - Engine ground 3 (B135) No. 63 (-):
    Fuel injector #2 (B135) No. 8 (+) - Engine ground 3 (B135) No. 63 (-):
    Fuel injector #3 (B135) No. 9 (+) - Engine ground 3 (B135) No. 63 (-):
    Fuel injector #4 (B135) No. 22 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition While engine idling
  10. No. Waveform 10
    G12519037Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Starter switch (B134) No. 46 (+) - Engine ground 3 (B135) No. No. 63 (-):
    Starter relay control (B134) No. 62 (+) - Engine ground 3 (B135) No. 63 (-):
    Battery voltage (battery terminal) (+) - Battery (-):
    Measuring condition When engine is started
  11. Waveform 11
    G12519038Courtesy of SUBARU OF AMERICA, INC.
    Measured terminal Purge control solenoid valve (B135) No. 51 (+) - Engine ground 3 (B135) No. 63 (-):
    Measuring condition During execution of active test using Subaru Select Monitor
G12519039Courtesy of SUBARU OF AMERICA, INC.
G12519040Courtesy of SUBARU OF AMERICA, INC.
G12519041Courtesy of SUBARU OF AMERICA, INC.
G12519042Courtesy of SUBARU OF AMERICA, INC.
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