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Signal Specification, Engine Control Module

General 

All values given below are between the terminals stated in column 1 and breakout box terminal #B2. Control module terminals #A1-#A60 correspond to terminals #A1-#A60 on the breakout box, terminals #A61-#A70 correspond to terminals #B1-#B10 on the breakout box and terminals #B1-#B50 correspond to terminals #B10-#B60 on the breakout box.

NOTE:

It is important to connect the breakout box and check the ground terminals before taking readings.

HINT: If the numbering of the connector is different from the numbering on the breakout box, the connector number is given first, terminal #A61, followed by the breakout box number in brackets, (terminal #B1). Example: #A61 (#B1). 

U= DC voltage in volts (V) U A/C = AC voltage in volts (V)
Ubat = Battery voltage in volts (V) f = Frequency in Hertz (Hz)
Ulow = Voltage approximately 0 V %pulse = Pulse ratio (%)
t = Time in milliseconds (ms)
CONNECTOR TERMINALS #A1-#A70

Terminal  Breakout box  Signal type  Ignition on  Idle  Other 
#A1 (#A1) - - - -
#A2 (#A2) Control signal
Canister purge (CP) valve
U = Ubat - Pulse width modulation (PWM) signal during activation of the EVAP canister shut-off valve
#A3 (#A3) - - - -
#A4 (#A4) Signal (+)
intake temperature sensor, integrated in the mass air flow (MAF) sensor
- (+10°C) U=2.01 V
(+20°C) U=2.62 V
(+30°C) U=3.21 V
-
#A5 (#A5) - - - -
#A6 (#A6) - - - -
#A7 (#A7) Control signal to the engine cooling fan control module Pulse width modulation (PWM) signal
Ulow = 1.5 V
pulse ratio = 10 %-90 %
-
Uhigh = Ubat -1.5 V
f=100Hz
-
#A8 (#A8) - - - -
#A9 (#A9) - - - -
#A10 (#A10) - - - -
#A11 (#A11) Control signal
preheating rear heated oxygen sensor (HO2S)
U = Ubat Preheating OFF
U = Ubat
Preheating ON
U = Ulow
-
#A12 (#A12) Reset valve
camshaft
Pulse width modulation (PWM) signal
Utop = Ubat
t = 0.6 ms
pulse ratio = 14 %
Pulse width modulation (PWM) signal
Utop = Ubat -1 V
t=2 ms
pulse ratio = 50 %
The pulse ratio changes with engine speed (RPM)
#A13 (#A13) - - - -
#A14 (#A14) Control signal
injector 5
U = Ubat t = 2-3 ms t increases with engine speed (RPM) and load
#A15 (#A15) Control signal
injector 3
U = Ubat tlow = 2-3 ms t increases with engine speed (RPM) and load
#A16 (#A16) Control signal
injector 1
U = Ubat tlow = 2-3 ms t increases with engine speed (RPM) and load
#A17 (#A17) - - - -
#A18 (#A18) Control signal
preheating front heated oxygen sensor (HO2S)
U = Ubat Preheating OFF
U = Ubat
Preheating ON
U = Ubat
-
#A19 (#A19) - - - -
#A20 (#A20) - - - -
#A21 (#A21) Signal
A/C pressure sensor
U=0.9 V (at approximately 20°C) - U increases with increased pressure in the system
#A22 (#A22) Mass air flow (MAF) sensor signal U = 0.58 V U = 1.33 V
Unloaded, engine at operating temperature
U increases with increasing air mass
#A23 (#A23) Signal
manifold absolute pressure (MAP) sensor
U = 1.64 V
atmospheric pressure at sea level
- U increases with increasing
pressure in the intake manifold
#A24 (#A24) Signal (+)
front heated oxygen sensor (HO2S) signal (+)
- λ=0.95 V>700 mV
λ=1.10 V<200 mV
-
#A25 (#A25) - - - -
#A26 (#A26) - - - -
#A27 (#A27) - - - -
#A28 (#A28) Signal
ignition discharge module (IDM) check, ignition coils
- - -
#A29 (#A29) Control signal
ignition coil no. 3
U = Ulow U = 2.5 volt
thigh = 2 ms
The frequency varies according to engine speed (RPM)
#A30 (#A30) Control signal
ignition coil no. 2
U = Ulow U = 2.5 volt
thigh = 2 ms
The frequency varies according to engine speed (RPM)
#A31 (#A31) Control signal
ignition coil no. 1
U = Ulow U = 2.5 volt
thigh = 2.5 ms
The frequency varies according to engine speed (RPM)
#A32 (#A32) - - - -
#A33 (#A33) Control signal
injector 4
U = Ubat tlow = 2-3 ms t increases with engine speed (RPM) and load
#A34 (#A34) Control signal
injector 2
U = Ubat tlow = 2-3 ms t increases with engine speed (RPM) and load
#A35 (#A35) - - - -
#A36 (#A36) Power ground
preheating, front heated oxygen sensor (HO2S)
U = Ulow - -
#A37 (#A37) Communication cable
control modules (CAN H)
- - Between the engine control module (ECM) and the throttle unit
#A38 (#A38) Control signal
stop lamp switch
U = Ulow (not activated)
U = Uhigh (activated)
- Between the engine control module (ECM) and the throttle unit
#A39 (#A39) Oil pressure switch U = Ulow (no oil pressure) U = Ubat -
#A40 (#A40) Signal (+)
engine coolant temperature (ECT) sensor
- (+20°C) U = 3.1 V
(+30°C) U = 2.6 V
(+80°C) U = 0.9 V
(+100°C) U = 0.5 V
-
#A41 (#A41) Signal (-)
front heated oxygen sensor (HO2S)
- λ=1 when the current is approximately +0.2 mA Negative current when the fuel air mixture is rich. Range: [-12 mA, +12 mA]
#A42 (#A42) Signal (+)
front heated oxygen sensor (HO2S)
- λ= 1 when the current is approximately +0.2 mA Positive current when the fuel air mixture is lean. Range: [-12 mA, +12 mA]
#A43 (#A43) - - - -
#A44 (#A44) - - - -
#A45 (#A45) - - - -
#A46 (#A46) Signal (+)
knock sensor (KS)
- - -
#A47 (#A47) Signal (+)
camshaft position (CMP) sensor
U≈5 V or U=Ulow f≈35 Hz
U≈2.5 V
The frequency increases with engine speed (RPM)
#A48 (#A48) Signal (+)
flywheel sensor
U=2.5 V U = sine wave voltage
Utop = 3.5 V
Uoffset = 2.5 V
-
#A49 (#A49) - - - -
#A50 (#A50) Control signal
ignition coil no. 5
U = Ulow U = 2.5 volt
thigh = 2 ms
The frequency varies according to engine speed (RPM)
#A51 (#A51) Control signal
ignition coil no. 4
U = Ulow U = 2.5 volt
thigh = 2 ms
The frequency varies according to engine speed (RPM)
#A52 (#A52) Control signal
Air assisted control valve (AACV)
- - -
#A53 (#A53) Power ground 3 Ulow - -
#A54 (#A54) Power ground 2 Ulow - -
#A55 (#A55) Communication cable
control modules (CAN L)
- - Between the engine control module (ECM) and the throttle unit
#A56 (#A56) Control signal
accelerator pedal (AP) position sensor, pulse width modulation (PWM) signal
Utop = 12 V
t = 4 ms
pulse ratio = 8 %-88 %
- Between the engine control module (ECM) and the throttle unit
#A57 (#A57) Power supply, camshaft position (CMP) sensor U =5 V - -
#A58 (#A58) Power supply, manifold absolute pressure (MAP) sensor
A/C pressure sensor
U =5 V - -
#A59 (#A59) - - - -
#A60 (#A60) Signal ground
mass air flow (MAF) sensor
U = Ulow - -
#A61 (#B1) Signal ground
intake temperature
engine coolant temperature (ECT) sensor
rear heated oxygen sensor (HO2S)
U = Ulow - -
#A62 (#B2) Power ground 1 U = Ulow - -
#A63 (#B3) - - - -
#A64 (#B4) Signal (-)
knock sensor (KS)
- - -
#A65 (#B5) Signal ground
camshaft position (CMP) sensor
U = Ulow - -
#A66 (#B6) Signal ground
flywheel sensor
U = Ulow - -
#A67 (#B7) - - - -
#A68 (#B8) - - - -
#A69 (#B9) Control signal
preheating front heated oxygen sensor (HO2S)
U = Ubat Preheating off U = Ubat
Preheating U = Ubat
B+ from the system relay
#A70 (#B10) Power supply U = Ubat - B+ from the system relay
CONNECTOR TERMINALS #B1-#B50

Terminal  Breakout box  Signal type  Ignition on  Engine idling  Other 
#B1 (#B11) Communication cable
control modules (CAN L)
- - Between the engine control module (ECM) and the transmission control module (TCM)
#B2 (#B12) - -   -
#B3 (#B13) - - - -
#B4 (#B14) Signal ground
intake manifold air temperature sensor
fuel tank pressure sensor
clutch pedal sensor
brake pedal sensor
U = Ulow - -
#B5 (#B15) Signal ground
accelerator pedal (AP) position sensor
U = Ulow - -
#B6 (#B16) - - - -
#B7 (#B17) - - - -
#B8 (#B18) Coolant level sensor U = Ulow - -
#B9 (#B19) Power supply
accelerator pedal (AP) position sensor, analog sensor
U =5 V - -
#B10 (#B20) Power supply
fuel tank pressure sensor
U =5 V - -
#B11 (#B21) 30-supply (Power supply from the battery) U = Ubat - -
#B12 (#B22) - - - -
#B13 (#B23) Control modules communication cable (CAN H) - - Between the engine control module (ECM) and the transmission control module (TCM)
#B14 (#B24) - - - -
#B15 (#B25) Signal
clutch pedal sensor
U=3.3 V (unaffected)
U = 2.2 V (fully
depressed, 100 mm)
- Varies depending on the position of the clutch pedal
#B16 (#B26) Signal
brake sensor
U = 4.4 V (unaffected)
U = 3.9 V (25 mm depressed)
- Varies depending on the position of the brake pedal
#B17 (#B27) Signal
accelerator pedal (AP) position sensor, analog signal
U=0.4 V (idle)
U=4.4 V (wide open throttle (WOT))
- Varies depending on the position of the accelerator pedal (AP)
#B18 (#B28) - - - -
#B19 (#B29) - - - -
#B20 (#B30) - - - -
#B21 (#B31) - - - -
#B22 (#B32) Diagnostic lead C-link U=90 % of Ubat Other values apply if a generic fault-tracing instrument is connected to the data link connector (DLC) -
#B23 (#B33) Signal (+)
crank, +50 supply
U = Ulow U = Ulow U = Ubat at crank
#B24 (#B34) - - - -
#B25 (#B35) Signal (+)
accelerator pedal (AP) position sensor, Pulse width modulated (PWM) signal
Utop = Ubat
t = 4 ms
pulse ratio = 8-88%
- Between the accelerator pedal (AP) position sensor and the engine control module (ECM)
#B26 (#B36 Signal (+)
stop lamp switch
U = Ubat when the brake pedal is depressed
U = Ulow when the brake pedal is not depressed
- -
#B27 (#B37) - - - -
#B28 (#B38) - - - -
#B29 (#B39) Signal
outside temperature sensor
(0°C) U = 3.99 V
(+10°C) U = 3.53 V
(+20°C) U = 3.01 V
(+30°C) U = 2.47 V
- Temperature range: -50°C to +120°C
#B30 (#B40) - - - -
#B31 (#B41) Signal
fuel tank pressure sensor
U = 2.5 V at 1 kPa negative pressure
U=3.3 V at atmospheric pressure (0 kPa overpressure)
U=4.1 V at 1 kPa overpressure
- -
#B32 (#B42) - - - -
#B33 (#B43) - - - -
#B34 (#B44) - - - -
#B35 (#B45) - - - -
#B36 (#B46) - - - -
#B37 (#B47) Signal
ignition ON signal, +15 supply
U = Ubat - -
#B38 (#B48) System relay
control signal
U = Ulow U = Ulow Relay activated: U = Ulow
Relay not activated: U = Ubat
The system relay runs on (2-5 minutes)
#B39 (#B49) - - - -
#B40 (#B50) Control signal
EVAP canister shut-off valve
U=3.82 V - -
#B41 (#B51) - - - -
#B42 (#B52) - - - -
#B43 (#B53) - - - -
#B44 (#B54) Control signal
A/C activation
U = Ubat (not activated)
U = Ulow (activated)
- -
#B45 (#B55) Control signal
fuel pump (FP) activation
Pulse width modulation (PWM) signal - Control signal to the central electronic module (CEM) to control the fuel pump (FP)
#B46 (#B56) Control signal
malfunction indicator lamp (MIL)
U = Ulow U = Ubat (not activated)
U = Ulow (activated)
-
#B47 (#B57) - - - -
#B48 (#B58) Control signal
engine start inhibiting
U = Ulow (activated)
U = Uhigh (not activated)
- Certain markets only.
The engine can only be started with the clutch pedal depressed (U=Ulow)
#B49 (#B59) - - - -
#B50 (#B60) - - - -