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Home >> Subaru >> 2005 >> Forester X, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Engine (Diagnostics) (H4SO) >> Engine Control Module (ECM) I/O Signal >> Electrical Specification
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Electrical Specification

Fig 1: Identifying Engine Control Module (ECM) Connectors
G03806000Courtesy of SUBARU OF AMERICA, INC.
ENGINE CONTROL MODULE (ECM) I/O SIGNAL 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 24 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 10 - 13 1 - 14 Waveform
Signal 2 B134 2 10 - 13 1 - 14 Waveform
Rear oxygen sensor heater signal B135 2 10 - 13 1 - 14 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 -
Camshaft position sensor Signal (+) B135 11 0 -7 - +7 Sensor output waveform
Signal (-) B135 23 0 0 -
Shield B135 31 0 0 -
Starter switch B137 8 0 0 Cranking: 8 - 14
A/C switch B137 16 ON: 10 - 13
OFF: 0
ON: 13 - 14
OFF: 0
-
A/C middle pressure switch B136 30 ON: 0
OFF: 10 - 13
ON: 0
OFF: 13 - 14
-
Ignition switch B137 15 10 - 13 13 - 14 -
Neutral position switch B137 9 ON: 0
OFF: 10 - 13
ON: 0
OFF: 13 - 14
-
Line end check connector B137 14 10 - 13 13 - 14 When connected: 0
Knock sensor Signal B136 25 2.5 2.5 -
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 -
Ignition control 1 B135 18 0 1 - 3.4 Waveform
2 B135 17 0 1 - 3.4 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 relay B135 26 ON: 0.5 or less
OFF: 10 - 13
ON: 0.5 or less
OFF: 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 B134 31 ON: 0.5 or less
OFF: 10 - 13
ON: 0.5 or less
OFF: 13 - 14
-
Radiator fan relay 2 control B135 34 ON: 0.5 or less
OFF: 10 - 13
ON: 0.5 or less
OFF: 13 - 14
Model with A/C only
Starter relay control B135 32 ON: 0.5 or less
OFF: 10 - 13
ON: 0.5 or less
OFF: 13 - 14
-
Self shut relay control B137 17 0.5 or less 0.5 or less -
Malfunction indicator light B134 17 - - Light "ON": 1 or less
Light "OFF": 10 - 14
Engine speed output B134 23 - 0 - 13 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 3.4 - 3.8 1.4 - 1.8 -
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 0.3 - 4.5 0.3 - 4.5 -
Fuel temperature sensor signal B136 12 1 - 4 1 - 4 -
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 - 2.7 - 2.9 -
Front oxygen (A/F) sensor signal (-) B134 26 - 2.35 - 2.55 -
Front oxygen (A/F) sensor shield B134 25 0 0 -
SSM/GST communication line B137 20 Less than 1 < More than 4 Less than 1 < More than 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 -
GND (Electronic throttle control motor) B137 3 0 0 -
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) B136 35 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 frequent: 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
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
-
Cruise control set light B134 16 ON: 0
OFF: 10 - 13
ON: 0
OFF: 13 - 14
-
Main light B134 15 ON: 0
OFF: 10 - 13
ON: 0
FF: 13 - 14
-
Clutch switch B136 10 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 1 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 -
EGR solenoid valve Signal 1 B134 11 0 or 10 - 13 0 or 10 - 14 -
Signal 2 B134 10 0 or 10 - 13 0 or 10 - 14 -
Signal 3 B134 9 0 or 10 - 13 0 or 10 - 14 -
Signal 4 B134 8 0 or 10 - 13 0 or 10 - 14 -