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Home >> Subaru >> 2016 >> Forester 2.0XT Premium >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 2 (Engine Controls (Diagnostics) (H4DO)) >> Engine Control Module (ECM) I/O Signal >> Electrical Specification
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Electrical Specification

WARNING: This page is about a different variant/trim than selected.
Fig 1: Identifying Engine Control Module I/O Signal Connector Terminal
G10409579Courtesy 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 0 -7 - +7 *1: Waveform
Signal (-) B136 27 0 0 -
Shield B136 35 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 -
Shield B136 30 0 0 -
Rear oxygen sensor Signal B136 21 0 0 - 0.9 -
Shield B136 30 0 0 -
Front oxygen (A/F) sensor heater signal B136 5 - - Waveform
Rear oxygen sensor heater signal B134 6 0 - 13 - Waveform
Engine coolant temperature sensor Signal B134 30 1 - 1.4 1 - 1.4 -
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 - 1.4 -
Starter switch B137 17 0 0 Model without push button start Cranking: Battery voltage Model with push button start
Cranking: Waveform
Accessory cut request B135 32 Battery voltage Battery voltage Model with push button start
Cranking: 0
Starter switch 2 B137 14 0 0 Model with push button start
Cranking: Battery voltage
Starter cut relay B135 34 0 0 Model with push button start Cranking: Battery voltage
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 Ignition switch "OFF": 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 ON: 0.5 or less
OFF: 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 - 13 or more Model with push button start Waveform
Purge control solenoid valve B134 11 ON: 1 or less
OFF: Battery voltage
ON: 1 or less
OFF: Battery voltage
Waveform
EGR control valve Signal 1 B136 11 0 or battery voltage 0 or battery voltage -
Signal 2 B136 13 0 or battery voltage 0 or battery voltage -
Signal 3 B136 31 0 or battery voltage 0 or battery voltage -
Signal 4 B136 32 0 or battery voltage 0 or battery voltage -
Manifold absolute pressure sensor signal B136 20 3.4 - 3.8 1.1 - 1.6 -
Electronic throttle control Main B134 18 Approx.0.7 Approx. 0.6 - 0.7 Fully closed: Approx.0.6
Fully open: Approx. 4
Sub 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 ON: 0
OFF: Battery voltage
ON: 0
OFF: Battery voltage
When ignition switch is turned to
ON: ON
Intake oil control solenoid (LH) B134 16 ON: 0
OFF: Battery voltage
ON: 0
OFF: Battery voltage
-
Intake oil control solenoid (RH) B134 17 ON: 0
OFF: Battery voltage
ON: 0
OFF: Battery voltage
-
Intake camshaft position sensor (LH) B136 15 0 or 5 0 or 5 *1: Waveform
Intake camshaft position sensor (RH) B136 26 0 or 5 0 or 5 *1: Waveform
Camshaft position sensor ground B136 34 0 0 -
Accelerator pedal position sensor Main sensor signal B135 23 Fully closed: 0.4 - 1
Fully open: 2.4 - 3.7
Fully closed: 0.4 - 1
Fully open: 2.4 - 3.7
-
Main power supply B135 21 5 5 -
Ground (main sensor) B135 29 0 0 -
Sub signal sensor B135 31 Fully closed: 0.3 - 1.1
Fully open: 2.3 - 3.8
Fully closed: 0.3 - 1.1
Fully open: 2.3 - 3.8
-
Starter relay B135 26 ON: 0
OFF: Battery voltage
ON: 0
OFF: Battery voltage
ON: Cranking
Clutch switch B137 15 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) B137 7 When brake pedal is depressed: 0
When brake pedal is depressed: 0
- When brake pedal is released:
Battery voltage
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 (Hi) B137 19 - - -
(Lo) B137 18 - - -
Self-shutoff control B135 13 0 0 -
Oil level switch B136 24 0 0 Oil level
LOW: Battery voltage
Generator control B135 18 0 - 6.5 0 - 6.5 -
Battery current sensor B137 11 2.6 - 2.8 2.4 - 2.6 New battery
Battery temperature sensor B137 24 1.1 - 2.4 1.1 - 2.4 When battery temperature is 20 - 50°C (68 - 122° F)
Tumble generator valve opening angle switch signal (LH) B136 9 Fully closed: 0.5 or less
Fully open: 4.5 or more
Fully closed: 0.5 or less
Fully open: 4.5 or more
-
Tumble generator valve (LH open) B134 23 0 or battery voltage 0 or battery voltage -
Tumble generator valve (LH closed) B134 24 0 or battery voltage 0 or battery voltage -
Tumble generator valve opening angle switch signal (RH) B136 23 Fully closed: 0.5 or less
Fully open: 4.5 or more
Fully closed: 0.5 or less
Fully open: 4.5 or more
-
Tumble generator valve (RH open) B134 25 0 or battery voltage 0 or battery voltage -
Tumble generator valve (RH closed) B134 14 0 or battery voltage 0 or battery voltage -
Immobilizer communication B135 25 - - -
ELCM Switching valve B135 1 Battery voltage Battery voltage Operating: 0
Pressure sensor B135 20 1 - 4 1 - 4 When ignition switch is turned to ON: atmospheric pressure
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.
  • 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.

*1: Waveform 

Fig 2: Crankshaft Position Sensor Waveform
G08570385Courtesy of SUBARU OF AMERICA, INC.
Measured terminal Crankshaft position sensor (B136) No. 16 - Engine ground 3 (B136) No. 1:
Intake camshaft position sensor RH (B134) No. 26 - Engine ground 3 (B136) No. 1:
Intake camshaft position sensor LH (B158) No. 15 - Engine ground 3 (B136) No. 1:
Measuring condition While engine idling
Fig 3: Electronic Throttle Control Network Diagram
G08580646Courtesy of SUBARU OF AMERICA, INC.
Fig 4: Leak Check Valve Assy Network Diagram
G10409582Courtesy of SUBARU OF AMERICA, INC.
Fig 5: Engine Ground Network Diagram
G09479337Courtesy of SUBARU OF AMERICA, INC.
Fig 6: Main Relay Network Diagram
G10409584Courtesy of SUBARU OF AMERICA, INC.