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Home >> Subaru >> 2005 >> Forester XT, Automatic >> 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 (ECM) Connector Terminals
G03806923Courtesy of SUBARU OF AMERICA, INC.
ENGINE CONTROL MODULE (ECM) CONNECTOR TERMINALS ELECTRICAL SPECIFICATION

Content Connector No. Terminal No. Signal (V) Note
Ignition SW ON (Engine OFF) Engine ON (Idling)
Crankshaft position sensor Signal (+) B135 10 0 -7 - +7 Sensor output waveform
Signal (-) B135 22 0 0 -
Shield B135 31 0 0 -
Rear oxygen sensor Signal B137 25 0 0 - 0.9 -
Shield B137 31 0 0 -
GND (sensor) B136 35 0 0 -
Front oxygen (A/F) sensor heater Signal 1 B134 3 0 - 1.0 - Sensor output waveform
Signal 2 B134 2 0 - 1.0 - Sensor output waveform
Rear oxygen sensor heater signal B135 2 0 - 1.0 - Sensor output waveform
Engine coolant temperature sensor Signal B136 14 1.0 - 1.4 1.0 - 1.4 After warm-up the engine.
GND (sensor) B136 35 0 0 After warm-up the engine.
Vehicle speed signal B135 27 0 or 5 0 or 5 "5" and "0" are repeatedly displayed when vehicle is driven.
Mass air flow sensor Signal B136 23 - 0.3 - 4.5 -
Shield B136 32 0 0 -
GND B136 31 0 0 -
Intake air temperature sensor signal B136 13 0.3 - 4.6 0.3 - 4.6 -
Exhaust temperature sensor Signal B136 24 - - -
GND (sensor) B136 35 0 0 -
Tumble generator valve position sensor RH Signal B136 27 Fully closed: 3.8 - 4.9 Fully opened: 0.2 - 0.9 -
Power supply B136 16 5 5 -
GND (sensor) B136 35 0 0 -
Tumble generator valve position sensor LH Signal B136 26 Fully closed: 3.8 - 4.9 Fully opened: 0.2 - 0.9 -
Power supply B136 16 5 5 -
GND (sensor) B136 35 0 0 -
Tumble generator valve RH (open) B134 9 0 or 10 - 13 0 or 13 - 14 Sensor output waveform
Tumble generator valve RH (close) B134 8 0 or 10 - 13 0 or 13 - 14 Sensor output waveform
Tumble generator valve LH (open) B134 11 0 or 10 - 13 0 or 13 - 14 Sensor output waveform
Tumble generator valve LH (close) B134 10 0 or 10 - 13 0 or 13 - 14 Sensor output waveform
Wastegate control solenoid valve B134 32 0 or 10 - 13 0 or 13 - 14 Sensor output waveform
Starter switch B137 8 0 0 Cranking: 8 - 14
A/C switch B137 16 ON: 10 - 13 OFF: 0 ON: 13 - 14 OFF: 0 -
Ignition switch B137 15 10 - 13 13 - 14 -
Neutral position switch B137 9 ON: 10 - 13 OFF: 0 ON: 13 - 14 OFF: 0 -
Test mode connector B137 14 10 - 13 13 - 14 When connected: 0
Knock sensor Signal B136 25 2.8 2.8 -
Shield B136 33 0 0 -
Back-up power supply B135 19 10 - 13 13 - 14 Ignition switch "OFF": 10 - 13
Control unit power supply B135 5 10 - 13 13 - 14 -
B135 6 10 - 13 13 - 14 -
Sensor power supply B136 16 5 5 -
Ignition control #1 B135 18 0 13 - 14 Waveform
#2 B135 17 0 13 - 14 Waveform
#3 B135 16 0 13 - 14 Waveform
#4 B135 15 0 13 - 14 Waveform
Fuel injector #1 B136 6 10 - 13 1 - 14 Waveform
#2 B136 5 10 - 13 1 - 14 Waveform
#3 B136 4 10 - 13 1 - 14 Waveform
#4 B136 3 10 - 13 1 - 14 Waveform
Fuel pump control unit Signal 1 B135 26 0 or 5 0 or 5 Sensor output waveform
Signal 2 B137 28 10 - 13 13 - 14 -
A/C relay control B135 33 ON: 0.5 or less OFF: 10 - 13 ON: 0.5 or less OFF: 13 - 14 -
Radiator fan relay 1 control B135 25 ON: 0.5 or less OFF: 10 - 13 ON: 0.5 or less OFF: 13 - 14 -
Radiator fan relay 2 control B135 24 ON: 0.5 or less OFF: 10 - 13 ON: 0.5 or less OFF: 13 - 14 Model with A/C only
Malfunction indicator light B134 17 - - Light "ON": 1 or less Light "OFF": 10 - 14
Engine speed output B134 23 - 0 - 13, or more Waveform
Purge control solenoid valve B134 14 ON: 1 or less OFF: 10 - 13 ON: 1 or less OFF: 13 - 14 Sensor output waveform
Manifold absolute pressure sensor Signal B136 22 1.7 - 2.4 1.1 - 1.6 -
Power supply B136 16 5 5
GND (sensor) B136 35 0 0
Fuel tank pressure sensor Signal B136 21 2.3 - 2.7 2.3 - 2.7 The valve operates when fuel filler cap is removed and reinstalled.
GND (sensor) B136 35 0 0 -
Fuel tank pressure control solenoid valve B134 12 ON: 1 or less OFF: 10 - 13 ON: 1 or less OFF: 13 - 14 -
Drain valve B134 13 ON: 1 or less OFF: 10 - 13 ON: 1 or less OFF: 13 - 14 -
Fuel tank sensor control valve B134 24 ON: 1 or less OFF: 10 - 13 ON: 1 or less OFF: 13 - 14 -
Fuel level sensor B136 20 0.12 - 4.75 0.12 - 4.75 -
Fuel temperature sensor signal B136 12 2.5 - 3.8 2.5 - 3.8 Ambient temperature: 25°C (75°F)
Blow-by leak diagnosis signal B137 24 0 0 When disconnection (malfunction): 5
Small light switch B137 12 ON: 0 OFF: 10 - 13 ON: 0 OFF: 13 - 14 -
Blower fan switch B137 13 ON: 0 OFF: 10 - 13 ON: 0 OFF: 13 - 14 -
Rear defogger switch B137 11 ON: 0 OFF: 10 - 13 ON: 0 OFF: 13 - 14 -
Power steering oil pressure switch B137 10 10 - 13 ON: 0 OFF: 13 - 14 -
Front oxygen (A/F) sensor signal (+) B134 33 2.8 - 3.2 2.8 - 3.2 -
Front oxygen (A/F) sensor signal (-) B134 26 2.4 - 2.7 2.4 - 2.7 -
Front oxygen (A/F) sensor shield B134 25 0 0 -
SSM/GST communication line B137 20 1 < --> 4 1 < --> 4 -
GND (injectors) B137 7 0 0 -
GND (ignition system) B135 12 0 0 -
GND (power supply) B135 4 0 0 -
B135 1 0 0 -
GND (control systems) B137 1 0 0 -
B137 2 0 0 -
GND (front oxygen (A/F) sensor heater 1) B134 7 0 0 -
GND (front oxygen (A/F) sensor heater 2) B134 6 0 0 -
Camshaft position sensor (LH) B135 8 0 - 0.9 ON: 0 OFF: 4.7 - 5.3 Sensor output waveform
Camshaft position sensor (RH) B135 9 0 - 0.9 ON: 0 OFF: 4.7 - 5.3 Sensor output waveform
Electronic throttle control Main B136 18 0.64 - 0.72 Fully opened: 3.96 0.64 - 0.72 (After engine warm-up) Fully closed: 0.6 Fully opened: 3.96
Sub B136 29 1.51 - 1.58 Fully opened: 4.17 1.51 - 1.58 (After engine warm-up) Fully closed: 1.48 Fully opened: 4.17
Power supply B136 16 5 5 -
GND (sensor) B137 3 0 0 -
Electronic throttle control motor (+) B137 5 Duty waveform Duty waveform Driving frequency: 500 Hz
Electronic throttle control motor (-) B137 4 Duty waveform Duty waveform Driving frequency: 500 Hz
Electronic throttle control motor power supply B137 6 10 - 13 13 - 14 -
Electronic throttle control motor relay B135 35 ON: 0 OFF: 10 - 13 ON: 0 OFF: 13 - 14 When ignition switch is ON: ON
Oil flow control solenoid valve (LH) Signal (+) B134 19 ON: 10 - 13 OFF: 0 ON: 13 - 14 OFF: 0 -
Signal (-) B134 29 0 0 -
Oil flow control solenoid valve (RH) Signal (+) B134 18 ON: 10 - 13 OFF: 0 ON: 13 - 14 OFF: 0 -
Signal (-) B134 28 0 0 -
Accelerator pedal position sensor Main B136 17 Fully closed: 1 Fully opened: 3.5 Fully closed: 1 Fully opened: 3.5 -
Power supply B136 15 5 5 -
GND (sensor) B136 34 0 0 -
Sub B136 28 Fully closed: 1 Fully opened: 3.5 Fully closed: 1 Fully opened: 3.5 -
Main light B134 15 ON: 0 OFF: 10 - 13 ON: 0 OFF: 13 - 14 -
Cruise control set light B134 16 ON: 0 OFF: 10 - 13 ON: 0 OFF: 13 - 14 -
Clutch switch B134 1 When clutch pedal is depressed: 0 When clutch pedal is released: 10 - 13 When clutch pedal is depressed: 0 When clutch pedal is released: 13 - 14 -
SET/COAST switch B136 11 ON: 10 - 13 OFF: 0 ON: 13 - 14 OFF: 0 -
Brake switch 1 B136 9 When brake pedal is depressed: 0 When brake pedal is released: 10 - 13 When brake pedal is depressed: 0 When brake pedal is released: 13 - 14 -
Brake switch 2 B136 8 When brake pedal is depressed: 10 - 13 When brake pedal is released: 0 When brake pedal is depressed: 13 - 14 When brake pedal is released: 0 -
RESUME/ACCEL switch B136 10 ON: 10 - 13 OFF: 0 ON: 13 - 14 OFF: 0 -
Main switch B136 7 ON: 10 - 13 OFF: 0 ON: 13 - 14 OFF: 0 -
CAN communication Signal (+) B137 18 Pulse signal -
Signal (-) B137 26 Pulse signal -