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Home >> Subaru >> 2009 >> Forester XT >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Engine (Diagnostics) (H4DOTC) >> Engine Control Module (ECM) I/O Signal >> Electrical Specification
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Electrical Specification

Fig 1: Identifying Engine Control Module Connector Terminal
G05334606Courtesy of SUBARU OF AMERICA, INC.
CONNECTOR TERMINAL REFERENCE

Contents Connector No. Terminal No. Signal (V) Note
Ignition SW ON (engine OFF) Engine ON (idling)
Crankshaft position sensor Signal (+) B134 13 0 -7 - +7 Waveform
Signal (-) B134 14 0 0 -
Shield B134 24 0 0 -
Rear oxygen sensor Signal B135 4 0 0 - 0.9 -
Shield B135 1 0 0 -
GND (sensor) B135 30 0 0 -
Front oxygen (A/F) sensor heater Signal 1 B136 3 - - Waveform
Signal 2 B136 2 - - Waveform
Rear oxygen sensor heater signal B136 4 0 - 13 12 - 14 Waveform
Engine coolant temperature sensor Signal B134 34 1.0 - 1.4 1.0 - 1.4 After engine is warmed up.
GND (sensor) B134 29 0 0 After engine is warmed up.
Air flow sensor Signal B135 26 - 0.3 - 4.5 -
Shield B135 35 0 0 -
GND B135 34 0 0 -
Intake air temperature sensor signal B135 18 0.3 - 4.6 0.3 - 4.6 -
Wastegate control solenoid valve B137 27 0 or 10 - 13 0 or 12 - 14 Waveform
Starter switch B136 32 0 0 Cranking: 8 - 14
A/C switch B136 24 ON: 10 - 13
OFF: 0		 ON: 12 - 14
OFF: 0		 -
Ignition switch B135 19 10 - 13 12 - 14 -
Neutral position switch B136 31 ON: 0
OFF: 10 - 13		 ON: 0
OFF: 12 - 14		 -
Delivery (test) mode connector B135 27 10 - 13 13 - 14 When connected: 0
Knock sensor Signal B134 15 2.8 2.8 -
Shield B134 25 0 0 -
Back-up power supply B135 5 10 - 13 12 - 14 Ignition switch "OFF": 10 - 13
Control module power supply B134 7 10 - 13 12 - 14 -
B135 2 10 - 13 12 - 14 -
Sensor power supply B134 19 5 5 -
Ignition control #1 B137 18 0 12 - 14 Waveform
#2 B137 19 0 12 - 14 Waveform
#3 B137 20 0 12 - 14 Waveform
#4 B137 21 0 12 - 14 Waveform
Fuel injector #1 B137 8 10 - 13 1 - 14 Waveform
#2 B137 9 10 - 13 1 - 14 Waveform
#3 B137 10 10 - 13 1 - 14 Waveform
#4 B137 11 10 - 13 1 - 14 Waveform
Fuel pump control unit Signal 1 B135 33 10 - 13 12 - 14 -
Signal 2 B136 12 0 or 5 0 or 5 Waveform
A/C relay control B136 9 ON: 0.5 or less
OFF: 10 - 13		 ON: 0.5 or less
OFF: 12 - 14		 -
Radiator fan relay 1 control B136 18 ON: 0.5 or less
OFF: 10 - 13		 ON: 0.5 or less
OFF: 12 - 14		 -
Radiator fan relay 2 control B136 29 ON: 0.5 or less
OFF: 10 - 13		 ON: 0.5 or less
OFF: 12 - 14		 Model with A/C only
Malfunction indicator light B136 11 - - Light "ON": 1 or less Light "OFF": 10 - 14
Engine speed output B136 22 - 0 - 13 or more Waveform
Purge control solenoid valve 1 B137 29 ON: 1 or less
OFF: 10 - 13		 ON: 1 or less
OFF: 12 - 14		 Waveform
Purge control solenoid valve 2 B136 7 ON: 1 or less
OFF: 10 - 13		 ON: 1 or less
OFF: 12 - 14		 Waveform
Manifold absolute pressure sensor Signal B134 6 1.7 - 2.4 1.1 - 1.6 -
Power supply B134 19 5 5
GND (sensor) B134 29 0 0
Power steering oil pressure switch B134 33 10 - 13 ON: 0
OFF: 12 - 14		 -
Front oxygen (A/F) sensor signal (+) B135 9 2.8 - 3.2 2.8 - 3.2 -
Front oxygen (A/F) sensor signal (-) B135 8 2.4 - 2.7 2.4 - 2.7 -
Front oxygen (A/F) sensor shield B135 1 0 0 -
SSM/GST communication line B136 16 1 or less ↔ 4 or more 1 or less ↔ 4 or more -
Intake camshaft position sensor (LH) B134 21 0 or 5 0 or 5 Waveform
Intake camshaft position sensor (RH) B134 11 0 or 5 0 or 5 Waveform
Intake camshaft position sensor ground B134 22 0 0 -
Electronic throttle control Main B134 18 0.64 - 0.72
Fully opened: 3.96		 0.64 - 0.72
(After engine is warmed up).		 Fully closed: 0.6
Fully opened: 3.96
Sub B134 28 1.51 - 1.58
Fully opened: 4.17		 1.51 - 1.58
(After engine is warmed up).		 Fully closed: 1.48
Fully opened: 4.17
Power supply B134 19 5 5 -
GND (sensor) B134 29 0 0 -
Electronic throttle control motor (+) B137 5 Duty waveform Duty waveform Drive frequency: 500 Hz
Electronic throttle control motor (-) B137 4 Duty waveform Duty waveform Drive frequency: 500 Hz
Electronic throttle control motor power supply B136 1 10 - 13 12 - 14 -
Electronic throttle control motor relay B136 21 ON: 0
OFF: 10 - 13		 ON: 0
OFF: 12 - 14		 When ignition switch is turned to ON: ON
Intake oil flow control solenoid valve (LH) Signal (+) B137 15 ON: 10 - 13
OFF: 0		 ON: 12 - 14
OFF: 0		 -
Signal (-) B137 14 0 0 -
Intake oil flow control solenoid valve (RH) Signal (+) B137 17 ON: 10 - 13
OFF: 0		 ON: 12 - 14
OFF: 0		 -
Signal (-) B137 16 0 0 -
Accelerator pedal position sensor Main sensor signal B135 23 Fully closed: 1
Fully opened: 3.3		 Fully closed: 1
Fully opened: 3.3		 -
Main power supply B135 21 5 5 -
GND (main sensor) B135 29 0 0 -
Shield B136 6 0 0 -
Sub sensor signal B135 31 Fully closed: 1
Fully opened: 3.3		 Fully closed: 1
Fully opened: 3.3		 -
Sub power supply B135 22 5 5 -
GND (sub sensor) B135 30 0 0 -
Starter relay B136 20 ON: 0
OFF: 10 - 13		 ON: 0
OFF: 12 - 14		 ON: cranking
A/C middle pressure switch B136 33 ON: 0
OFF: 10 - 13		 ON: 0
OFF: 12 - 14		 -
Blower fan switch B135 11 ON: 0
OFF: 10 - 13		 ON: 0
OFF: 12 - 14		 Manual A/C model
Clutch switch B136 25 When clutch pedal is depressed: 0
When clutch pedal is released: 10 - 13		 When clutch pedal is depressed: 0
When clutch pedal is released: 12 - 14		 -
Brake switch 1 B135 20 When brake pedal is depressed: 0
When brake pedal is released: 10 - 13		 When brake pedal is depressed: 0
When brake pedal is released: 12 - 14		 -
Brake switch 2 B135 28 When brake pedal is depressed: 10 - 13
When brake pedal is released: 0		 When brake pedal is depressed: 12 - 14
When brake pedal is released: 0		 -
Cruise control command switch B135 24 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 B135 12 ON: 0
OFF: 5		 ON: 0
OFF: 5		 -
Fuel tank pressure sensor B135 32 2.3 - 2.7 2.3 - 2.7 -
Pressure control solenoid valve B136 28 ON: 1 or less
OFF: 10 - 13		 ON: 1 or less
OFF: 12 - 14		 -
Drain valve B136 17 ON: 1 or less
OFF: 10 - 13		 ON: 1 or less
OFF: 12 - 14		 -
Fuel temperature sensor B135 17 2.5 - 3.8 2.5 - 3.8 Ambient temperature: 25°C (77°F)
Immobilizer Signal 1 B136 26 - - -
Signal 2 B136 34 - - -
CAN communication (+) B136 27 - - -
CAN communication (-) B136 35 - - -
AT/MT identification B136 15 0 0 -
Blow-by leak diagnosis B134 30 0 0 At the time of open circuit (fault): 5
Tumble generator valve position sensor signal (RH) B134 26 Fully closed: 0.4 - 1.2
Fully opened: 2.8 - 4.6		 Fully closed: 0.4 - 1.2
Fully opened: 2.8 - 4.6		 -
Tumble generator valve position sensor signal (LH) B134 16 Fully closed: 0.4 - 1.2
Fully opened: 2.8 - 4.6		 Fully closed: 0.4 - 1.2
Fully opened: 2.8 - 4.6		 -
Tumble generator valve RH (closed) B137 23 0 or 10 - 13 0 or 12 - 14 -
Tumble generator valve LH (closed) B137 13 0 or 10 - 13 0 or 12 - 14 -
Tumble generator valve RH (open) B137 22 0 or 10 - 13 0 or 12 - 14 -
Tumble generator valve LH (open) B137 12 0 or 10 - 13 0 or 12 - 14 -
Secondary air pipe pressure sensor Signal B134 27 2.2 - 2.8 2.2 - 2.8 When secondary air is inducted: 3.2 - 4.9
Power supply B134 19 5.12 5.12 -
GND (sensor) B134 29 0 0 -
Secondary air combination valve relay 1 B135 15 ON: 0
OFF: 10 - 13		 ON: 0
OFF: 12 - 14		 -
Secondary air combination valve relay 2 B135 14 ON: 0
OFF: 10 - 13		 ON: 0
OFF: 12 - 14		 -
Secondary air pump relay B136 8 ON: 0
OFF: 10 - 13		 ON: 0
OFF: 12 - 14		 -
Self-shutoff control B136 23 10 - 13 12 - 14 -
GND (ignition system) B137 26 0 0 -
B137 6 0 0 -
Ground (engine 1) B134 5 0 0 -
Ground (engine 2) B137 7 0 0 -
Ground (engine 3) B137 2 0 0 -
Ground (engine 4) B137 1 0 0 -
Ground (engine 5) B137 3 0 0 -
Ground (body) B136 6 0 0 -
INPUT/OUTPUT REFERENCE CHART

Input/output name Measuring condition Waveform
1. Crankshaft position sensor At idling
G05334607Courtesy of SUBARU OF AMERICA, INC.
2. Camshaft position sensor At idling
G05334608Courtesy of SUBARU OF AMERICA, INC.
Fig 2: Engine Control Module (ECM) Circuit Diagram (1 Of 5)
G05955515Courtesy of SUBARU OF AMERICA, INC.
Fig 3: Engine Control Module (ECM) Circuit Diagram (2 Of 5)
G05661335Courtesy of SUBARU OF AMERICA, INC.
Fig 4: Engine Control Module (ECM) Circuit Diagram (3 Of 5)
G05661336Courtesy of SUBARU OF AMERICA, INC.
Fig 5: Engine Control Module (ECM) Circuit Diagram (4 Of 5)
G05661337Courtesy of SUBARU OF AMERICA, INC.
Fig 6: Engine Control Module (ECM) Circuit Diagram (5 Of 5)
G05955519Courtesy of SUBARU OF AMERICA, INC.
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