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Home >> Subaru >> 2017 >> Crosstrek Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics - Introduction) (H4DO) >> Engine Control Module (ECM) I/O Signal >> Electrical Specification >> Engine Control Module (ECM)
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Engine Control Module (ECM)

Fig 1: Engine Control Module Terminals
G10290804Courtesy of SUBARU OF AMERICA, INC.
Description Connector No. Terminal No. Signal (V) Note
Ignition SW ON (Engine OFF) Engine ON (Idling)
Crankshaft position sensor (+) signal B136 16 5 0 or 5 Waveform*
(-) signal B136 27 0 0 -
Front oxygen (A/F) sensor (+) signal B136 19 2.8 - 3.2 2.8 - 3.2 -
(-) signal B136 18 2.4 - 2.7 2.4 - 2.7 -
Rear oxygen sensor Signal B136 21 0 0 - 0.9 -
Front oxygen (A/F) sensor heater signal B136 5 Battery voltage 0 or battery voltage Waveform
Rear oxygen sensor heater signal B134 6 Battery voltage 0 or battery voltage Waveform
Oxygen sensor Shield B136 30 0 0 -
Engine coolant temperature sensor Signal B134 30 1 - 1.4 1 - 1.6 -
Air flow sensor Signal B137 22 - 0.3 - 4.5 -
Shield B137 28 0 0 -
Ground B137 29 0 0 -
Intake air temperature sensor signal B137 12 0.3 - 4.6 0.3 - 4.6 -
Engine oil temperature sensor signal B134 20 1 - 1.4 1 - 1.6 -
Starter switch B137 17 Waveform Waveform Model without push button start: Waveform Models with push button start: Waveform
Accessory cut request B135 32 Waveform Waveform Model without push button start: Waveform Models with push button start: Waveform
Starter switch 2 B137 14 Waveform Waveform Model without push button start: Waveform Models with push button start: Waveform
Starter cut relay B135 34 Waveform Waveform Model without push button start: Waveform Models with push button start: Waveform
Ignition switch B137 27 Battery voltage Battery voltage -
Neutral position switch B137 16 ON: 0
OFF: Battery voltage
ON: 0
OFF: Battery voltage
-
Delivery mode switch B137 13 Battery voltage Battery voltage When fuse is installed: 0
Knock sensor Signal B136 28 2.5 2.5 -
Shield B136 29 0 0 -
Back-up power supply B137 2 Battery voltage Battery voltage -
Control module power supply B136 6 Battery voltage Battery voltage -
B137 1 Battery voltage Battery voltage -
Sensor power supply B134 19 5 5 -
B135 22 5 5 -
Ignition control #1 B134 21 0 0 or 5 Waveform
#2 B134 10 0 0 or 5 Waveform
#3 B134 31 0 0 or 5 Waveform
#4 B134 8 0 0 or 5 Waveform
Fuel injector #1 B134 12 Battery voltage 0 or battery voltage Waveform
#2 B134 22 Battery voltage 0 or battery voltage Waveform
#3 B134 32 Battery voltage 0 or battery voltage Waveform
#4 B134 13 Battery voltage 0 or battery voltage Waveform
Fuel pump relay control B135 19 Battery voltage ON: 0.5 or less
OFF: Battery voltage
-
A/C relay control B135 35 ON: 0.5 or less
OFF: Battery voltage
ON: 0.5 or less
OFF: Battery voltage
-
A/C switch B137 26 ON: Battery voltage
OFF: 0
ON: Battery voltage
OFF: 0
Manual A/C model
Blower fan switch B137 20 ON: 0
OFF: Battery voltage
ON: 0
OFF: Battery voltage
Manual A/C model
A/C middle pressure switch B137 8 ON: 0
OFF: Battery voltage
ON: 0
OFF: Battery voltage
-
Main fan relay control B135 12 ON: 0.5 or less
OFF: Battery voltage
ON: 0.5 or less
OFF: Battery voltage
-
Sub fan relay control B135 11 ON: 0.5 or less
OFF: Battery voltage
ON: 0.5 or less
OFF: Battery voltage
-
Engine speed output B135 15 - 0 or battery voltage Waveform
Purge control solenoid valve B134 11 Battery voltage Battery voltage When in operation: 0 or battery voltage
EGR control valve Signal 1 B136 11 Battery voltage 0 or battery voltage -
Signal 2 B136 13 Battery voltage 0 or battery voltage -
Signal 3 B136 31 Battery voltage 0 or battery voltage -
Signal 4 B136 32 Battery voltage 0 or battery voltage -
Manifold absolute pressure sensor signal B136 20 3.4 - 3.8 1 - 1.6 -
Electronic throttle control Main signal B134 18 Approx. 0.7 Approx. 0.6 - 0.7 Fully closed: Approx. 0.6
Fully open: Approx. 4.0
Sub signal B134 28 Approx. 1.6 Approx. 1.5 - 1.6 Fully closed: Approx. 1.5
Fully open: Approx. 4.2
Electronic throttle control motor (+) B134 2 Duty waveform Duty waveform Drive frequency: 500 Hz
Electronic throttle control motor (-) B134 1 Duty waveform Duty waveform Drive frequency: 500 Hz
Electronic throttle control motor power supply B135 7 Battery voltage Battery voltage -
Electronic throttle control motor relay B135 17 0 0 -
Intake oil control solenoid RH B134 17 Battery voltage 0 or battery voltage Waveform
Intake oil control solenoid LH B134 16 Battery voltage 0 or battery voltage Waveform
Exhaust oil control solenoid RH B134 7 Battery voltage 0 or battery voltage Waveform
Exhaust oil control solenoid LH B134 5 Battery voltage 0 or battery voltage Waveform
Intake camshaft position sensor RH B136 26 0 or 5 0 or 5 Waveform*
Intake camshaft position sensor LH B136 15 0 or 5 0 or 5 Waveform*
Exhaust camshaft position sensor RH B136 14 0 or 5 0 or 5 Waveform*
Exhaust camshaft position sensor LH B136 25 0 or 5 0 or 5 Waveform*
Camshaft position sensor ground B136 34 0 0 -
Accelerator pedal position sensor Main signal B135 23 Fully closed: 0.4 - 1
Fully opened: 2.4 - 3.7
Fully closed: 0.4 - 1
Fully opened: 2.4 - 3.7
-
Main power supply B135 21 5 5 -
Ground (main) B135 29 0 0 -
Sub signal B135 31 Fully closed: 0.3 - 1.1
Fully opened: 2.3 - 3.8
Fully closed: 0.3 - 1.1
Fully opened: 2.3 - 3.8
-
Starter relay B135 26 Waveform Waveform Model without push button start: Waveform Models with push button start: Waveform
Clutch switch B137 15 ON: 0
OFF: Battery voltage
ON: 0
OFF: Battery voltage
-
Brake switch 1 (Brake switch) B137 7 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) B137 3 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 command switch B137 30 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
-
Cruise control main switch B137 23 ON: 0
OFF: 5
ON: 0
OFF: 5
-
CAN communication (MAIN-CAN) (Hi) B137 19 - - -
(Lo) B137 18 - - -
Self-shutoff control B135 13 0 0 -
Generator control B135 18 0 or 6.5 0 or 6.5 Waveform
Battery current sensor B137 11 2.6 - 2.8 2.4 - 2.6 -
Battery temperature sensor B137 24 1.1 - 2.4 1.1 - 2.4 When battery temperature is 20 - 50°C (68 - 122°F)
Oil level switch B136 24 0 0 Oil level LOW:
Battery voltage
Tumble generator valve opening angle switch signal RH B136 23 0 Fully closed: 0.5 or less
Fully opened: 4.5 or more
When in operation: Waveform
Tumble generator valve actuator RH open B134 25 0 0 When in operation: Waveform
Tumble generator valve actuator RH closed B134 14 0 0 When in operation: Waveform
Tumble generator valve opening angle switch signal LH B136 9 0 Fully closed: 0.5 or less
Fully opened: 4.5 or more
When in operation: Waveform
Tumble generator valve actuator LH open B134 23 0 0 When in operation: Waveform
Tumble generator valve actuator LH closed B134 24 0 0 When in operation: Waveform
Immobilizer communication B135 25 - - -
Leak check valve assembly Switching valve B135 1 Battery voltage Battery voltage Operating: 0
Pressure sensor B135 20 1 - 4 1 - 4 -
Vacuum pump B135 8 Battery voltage Battery voltage Operating: 0
Ground Sensor B134 29 0 0 -
B135 30 0 0 -
Engine 1 B134 4 0 0 -
Engine 2 B134 3 0 0 -
Engine 3 B136 1 0 0 -
Engine 4 B136 2 0 0 -
Engine 5 B136 3 0 0 -
Body B137 4 0 0 -
NOTE:
  • Perform measurement after warming up the engine.
  • 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.

*Waveform

Fig 2: Crankshaft Position Sensor Waveform
G11590045Courtesy of SUBARU OF AMERICA, INC.
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 appear as shown in figure (B) when measured by the Subaru Select Monitor oscilloscope function.

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.

Fig 3: Crankshaft Position Sensor Waveform
G11590046Courtesy of SUBARU OF AMERICA, INC.
Measured terminal Crankshaft position sensor (+) signal (B136) No. 16 (+) - Engine ground 3 (B136) No. 1 (-):
Intake camshaft position sensor RH (B136) No. 26 (+) - Engine ground 3 (B136) No. 1 (-):
Intake camshaft position sensor LH (B136) No. 15 (+) - Engine ground 3 (B136) No. 1 (-):
Exhaust camshaft position sensor RH (B136) No. 14 (+) - Engine ground 3 (B136) No. 1 (-):
Exhaust camshaft position sensor LH (B136) No. 25 (+) - Engine ground 3 (B136) No. 1 (-):
Measuring condition While engine idling
Fig 4: Engine Control Module I/O Signal Circuit Diagram (1 Of 4)
G10320234Courtesy of SUBARU OF AMERICA, INC.
Fig 5: Engine Control Module I/O Signal Circuit Diagram (2 Of 4)
G10320235Courtesy of SUBARU OF AMERICA, INC.
Fig 6: Engine Control Module I/O Signal Circuit Diagram (3 Of 4)
G10320236Courtesy of SUBARU OF AMERICA, INC.
Fig 7: Engine Control Module I/O Signal Circuit Diagram (4 Of 4)
G10320237Courtesy of SUBARU OF AMERICA, INC.