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Home >> Subaru >> 2007 >> Impreza WRX STi >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls (Diagnostics) (STI) >> Engine Control Module (ECM) I/O Signal >> Electrical Specification
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Electrical Specification

Fig 1: Identifying Engine Control Module (ECM) Connector Terminals
G05334606Courtesy of SUBARU OF AMERICA, INC.
ECM CONNECTOR DESCRIPTION

Description Connector No. Terminal No. Signal (V) Note
Ignition SW ON (engine OFF) Engine ON (idling)
Crankshaft position sensor Signal (+) B134 13 0 -7 -+7 Sensor output 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 0 - 1.0 - Sensor output waveform
Signal 2 B136 2 0-1.0 - Sensor output waveform
Rear oxygen sensor heater signal B136 4 0-1.0 - Sensor output 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.
Vehicle speed signal B136 13 0 or 5 0 or 5 "5" and "0" are repeatedly displayed when vehicle is driven.
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 -
Tumble generator valve position sensor RH Signal B134 26 Fully closed: 0.4 - 1.2
Fully opened: 2.8 - 4.6		 -
Power supply B134 19 5 5 -
GND (sensor) B134 29 0 0 -
Tumble generator valve position sensor LH Signal B134 16 Fully closed: 0.4 - 1.2 Fully opened: 2.8 - 4.6 -
Power supply B134 19 5 5 -
GND (sensor) B134 29 0 0 -
Tumble generator valve RH (open) B137 22 0 or 10 - 13 0 or 12 - 14 Sensor output waveform
Tumble generator valve RH (closed) B137 23 0 or 10 - 13 0 or 12 - 14 Sensor output waveform
Tumble generator valve LH (open) B137 12 0 or 10 - 13 0 or 12 - 14 Sensor output waveform
Tumble generator valve LH (closed) B137 13 0 or 10 - 13 0 or 12 - 14 Sensor output waveform
Wastegate control solenoid valve B137 27 0 or 10- 13 0 or 12 - 14 Sensor output 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: 10 - 13 OFF: 0 ON: 12 - 14 OFF: 0 -
Test mode connector B135 27 10 - 13 12 - 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 -
Self-shutoff relay control B136 23 10 - 13 12 - 14 -
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 0 or 5 0 or 5 Sensor output waveform
Signal 2 B136 12 10 - 13 12 - 14 -
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 -
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 Sensor output waveform
Purge control solenoid valve 2 B136 7 ON: 1 or less OFF: 10 - 13 ON: 1 or less OFF: 12 - 14 Sensor output 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
Fuel tank pressure sensor Signal B135 32 2.3 - 2.7 2.3 - 2.7 Valve operates after removing fuel filler cap and installing again.
GND (sensor) B135 30 0 0 -
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 level sensor B135 10 0.12 - 4.75 0.12 - 4.75 -
Fuel temperature sensor signal B135 17 2.5 - 3.8 2.5 - 3.8 Ambient temperature: 25°C (77°F)
Blow-by leak diagnosis signal B134 30 0 0 At the time of open circuit (fault): 5
Small light switch B135 15 ON: 0 OFF: 10 - 13 ON: 0 OFF: 12 - 14 -
Blower fan switch B135 16 ON: 0 OFF: 10 - 13 ON: 0 OFF: 12 - 14 -
Rear defogger switch B135 14 ON: 0 OFF: 10 - 13 ON: 0 OFF: 12 - 14 -
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 -
GND (engine 4) B137 1 0 0 -
GND (power supply) (Ignition 1) B137 26 0 0 -
(Ignition 2) B137 6 0 0 -
GND (engine 3) B137 2 0 0 -
GND (engine 5) B137 3 0 0 -
GND (body) B136 6 0 0 -
GND (engine 1) B134 5 0 0 -
GND (engine 2) B137 7 0 0 -
AT/MT identification B136 15 0 0 -
Camshaft position sensor (LH) B134 21 0 - 0.9 ON: 0 OFF: 4.7 -5.3 Sensor output waveform
Camshaft position sensor (RH) B134 11 0 - 0.9 ON: 0 OFF: 4.7 - 5.3 Sensor output waveform
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
AVCS solenoid (LH) Signal (+) B137 15 ON: 10 -13 OFF: 0 ON: 12 - 14 OFF: 0 -
Signal (-) B137 14 0 0 -
AVCS solenoid (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: 3.5		 Fully closed: 1
Fully opened: 3.5		 -
Main power supply B135 21 5 5 -
GND (main sensor) B135 29 0 0 -
Sub sensor signal B135 31 Fully closed: 1
Fully opened: 3.5		 Fully closed: 1
Fully opened: 3.5		 -
Sub power supply B135 22 5 5 -
GND (sub sensor) B135 30 0 0 -
Cruise control set light B135 3 ON: 0 OFF: 10 - 13 ON: 0 OFF: 12 - 14 -
Main light B135 6 ON: 0 OFF: 10 - 13 ON: 0 OFF: 12 - 14 -
Clutch switch B136 25 When clutch pedal is depressed: 0
When brake pedal is released: 10 - 13		 When clutch pedal is depressed: 0
When brake pedal is released: 12 - 14		 -
SET/COAST switch B135 24 ON: 10 -13 OFF: 0 ON: 12 - 14 OFF: 0 -
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		 -
RESUME/ACCEL switch B135 13 ON: 10 - 13 OFF: 0 ON: 12 -14 OFF: 0 -
Main switch B135 12 ON: 10 - 13 OFF: 0 ON: 12 - 14 OFF: 0 -
Secondary air pipe pressure sensor Signal B134 27 1.7 - 2.4 1.1 - 1.6 -
Power supply B134 19 5 5 -
GND (sensor) B134 29 0 0 -
Secondary air combination valve relay 1 B136 30 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 -
WAVEFORM REFERENCE

Input/output name Measuring condition Waveform
1. Crankshaft position sensor During idling
G05334607Courtesy of SUBARU OF AMERICA, INC.
2. Camshaft position sensor During idling
G05334608Courtesy of SUBARU OF AMERICA, INC.
Fig 2: Identifying Engine Control Module (ECM) I/O Signal - Circuit Diagram (1 Of 5)
G05334609Courtesy of SUBARU OF AMERICA, INC.
Fig 3: Identifying Engine Control Module (ECM) I/O Signal - Circuit Diagram (2 Of 5)
G05334299Courtesy of SUBARU OF AMERICA, INC.
Fig 4: Identifying Engine Control Module (ECM) I/O Signal - Circuit Diagram (3 Of 5)
G05334300Courtesy of SUBARU OF AMERICA, INC.
Fig 5: Identifying Engine Control Module (ECM) I/O Signal - Circuit Diagram (4 Of 5)
G05334612Courtesy of SUBARU OF AMERICA, INC.
Fig 6: Identifying Engine Control Module (ECM) I/O Signal - Circuit Diagram (5 Of 5)
G05334613Courtesy of SUBARU OF AMERICA, INC.
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