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Signal Specification

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General 

All values given below are between the terminals stated in column 1 and breakout box terminal in the Control unit) and breakout box terminal #B3 unless otherwise indicated in column 6 (Miscellaneous). Control module terminals #A1-#A70 correspond to terminals #A1-#B10 on the breakout box, terminals #B1-#B50 correspond to #B11 - #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, (#B1). Example: #A61 (#B1). 

U= DC voltage in volts (V) UAC = AC voltage in volts (V)
Ubat = Battery voltage (V) f = Frequency in Hertz (Hz)
Ulow = Voltage approximately 0 V % duty = Duty cycle (pulse ratio) as a percentage (%)
t = Time in milliseconds (ms) I = Current in amperes (A)
Control module terminal  Breakout box terminal  Signal type  Ignition on  Engine idling  Other 
#A1 #A1 Throttle unit signal, potentiometer 1 (circuit 1) U ≈ 0.4 -4 V - The voltage varies depending on the position of the throttle. U increases with throttle opening.
#A2 #A2 Fuel pressure sensor signal - 350 - 400 kPa
(absolute pressure)
U=1.8-2 V
The voltage increases with increased fuel pressure.
#A3 #A3 Fuel temperature sensor signal - U≈ 0.5 V- 4.5 V The voltage falls with increased fuel temperature.
The fuel temperature sensor is integrated in the fuel pressure sensor.
#A4 #A4 Engine coolant temperature (ECT) sensor signal - (+30°C) U=1.22 V
(+80°C) U = 0.29 V
(+100°C) U = 0.17 V
 
#A5 #A5 Intake air temperature (IAT) sensor signal - (+20°C) U = 3.50 V
(+30°C) U = 3.00 V
(+40°C) U = 2.50 V
The intake air temperature (IAT) sensor is integrated in the boost pressure sensor.
#A6 #A6 Control signal, rear heated oxygen sensor (HO2S) preheating U = Ubat Preheating off: U = Ubat
Preheating on U=Ulow
 
#A7 #A7 Engine cooling fan (FC) control signal Pulse width modulation (PWM) signal
Uhigh at least 70% of Ubat
Ulow = 1.2 V
f = 100 Hz
Pulse ratio = 10-95%
   
#A8 #A8 - - -  
#A9 #A9 Control signal, canister purge (CP) valve U = Ubat - PWM signal during activation of the canister purge (CP) valve
#A10 #A10 - - -  
#A11 #A11 - - -  
#A12 #A12 - - -  
#A13 #A13 Control signal, intake camshaft reset valve - Pulse width modulation (PWM) signal
Utop =Ubat
f=250 Hz (±12.5 Hz)
Pulse ratio 20-95%
The pulse ratio governs control of the camshaft
#A14 #A14 Injector no. 5 control signal U = Ubat t= 2-3 ms t increases with engine speed (RPM) and load
#A15 #A15 Injector no. 3 control signal U = Ubat t= 2-3 ms t increases with engine speed (RPM) and load
#A16 #A16 Injector no. 1 control signal U = Ubat t= 2-3 ms t increases with engine speed (RPM) and load
#A17 #A17 Power supply U = Ubat - Supplied via the system relay
#A18 #A18 Control signal, front heated oxygen sensor (HO2S) preheating U = Ubat Preheating off: U = Ubat
Preheating on: U=Ulow
 
#A19 #A19 Signal ground, throttle unit, potentiometers 1 and 2 U=Ulow -  
#A20 #A20 Throttle unit signal, potentiometer 2 (circuit 2) U ≈ 4 -0.4 V - The voltage varies depending on the position of the throttle. U decreases with increasing throttle opening.
#A21 #A21 Exhaust camshaft reset valve control signal - Pulse width modulation (PWM) signal
Utop =Ubat
f=250 Hz (±12.5 Hz)
Pulse ratio 20-95%
The pulse ratio governs control of the camshaft
#A22 #A22 Mass air flow (MAF) sensor signal U = 1 V U = 1.7 V U increases with increasing air mass
#A23 #A23 Boost pressure sensor signal U = 1.96 V - U increases with increasing boost pressure.
#A24 #A24 Front heated oxygen sensor (HO2S), pump current - - Pulsed current supply, not measured
#A25 #A25 - - -  
#A26 #A26 Oil pressure switch signal U=Ulow U = Ubat  
#A27 #A27 Signal camshaft position (CMP) sensor 2, exhaust camshaft U =5 V U = Pulsed signal
Utop =5 V
Uoffset = 2.5 V
The frequency varies according to engine speed (RPM)
#A28 #A28 Front heated oxygen sensor (HO2S), calibration current - - Not measured
#A29 #A29 Power supply, 5 V camshaft position (CMP) sensor U =5 V -  
#A30 #A30 Ignition coil no. 2 control signal U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A31 #A31 Ignition coil no. 1 control signal U=Ulow U=2.5 V
thigh =2.5 ms
The frequency varies according to engine speed (RPM)
#A32 #A32 - - -  
#A33 #A33 Injector no. 4 control signal U = Ubat tlow =2-3 ms t increases with engine speed (RPM) and load
#A34 #A34 Injector no. 2 control signal U = Ubat tlow =2-3 ms t increases with engine speed (RPM) and load
#A35 #A35 Control signal (+) damper motor for the throttle unit - Pulse width modulation (PWM) signal
Utop =Ubat
Pulse ratio 0-100%
The polarity of the control signal changes when the damper motor is deployed against the direction of rotation.
The damper motor is controlled using a pulse width modulation (PWM) signal from the integrated power stage in the engine control module (ECM) measured to terminal #A36 (#A36)
#A36 #A36 Control signal (-) damper motor for the throttle unit - Pulse width modulation (PWM) signal
Utop =Ubat
Pulse ratio 0-100%
The polarity of the control signal changes when the damper motor is deployed against the direction of rotation.
The damper motor is controlled using a pulse width modulation (PWM) signal from the integrated power stage in the engine control module (ECM) measured to terminal #A35 (#A35)
#A37 #A37 - - -  
#A38 #A38 Turbocharger (TC) control valve control signal U = Ubat - During turbocharger (TC) control: Pulse width modulation (PWM) signal
f = 32 Hz
#A39 #A39 Power supply 5 V
boost pressure sensor, air conditioning (A/C) pressure sensor, mass air flow (MAF) sensor, oil level sensor, fuel pressure sensor
U =5 V -  
#A40 #A40 Oil level sensor - Pulse width modulation (PWM) signal
Utop =5 V
Pulse ratio 17-83%
T=120 ms
Pulse train with three pulses, then pause for 1.2 seconds.
Pulse no. 1= oil temperature.
Pulse no. 2= oil level.
Pulse no. 3= oil grade.
The pulse ratio for each pulse changes depending on the present:
- oil temperature
- oil level
- oil grade.
The PWM signal is generated by the oil level sensor.
#A41 #A41 Signal (+), front heated oxygen sensor (HO2S) - - Pulsed current signal, not measured
#A42 #A42 Signal (-), front heated oxygen sensor (HO2S) - - Pulsed current signal, not measured
#A43 #A43 - - -  
#A44 #A44 - - -  
#A45 #A45 Signal (+), rear knock sensor (KS) U=Ulow -  
#A46 #A46 Signal (+) front knock sensor (KS) U=Ulow -  
#A47 #A47 Signal camshaft position (CMP) sensor 1, intake camshaft U =5 V U = Pulsed signal
Utop =5 V
Uoffset = 2.5V
The frequency varies according to engine speed (RPM)
#A48 #A48 Signal (+), flywheel sensor U=2.5 V U= sine wave voltage
Utop =5 V
Uoffset = 2.5 V
Measured to terminal #A66 #B6)
The frequency increases with engine speed (RPM)
#A49 #A49 - - -  
#A50 #A50 Ignition coil no. 3 control signal U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A51 #A51 Ignition coil no. 5 control signal U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A52 #A52 Ignition coil no. 4 control signal U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A53 #A53 Power ground 3 Ulow - Ground terminal, connected to the chassis
#A54 #A54 Power ground 2 Ulow - Ground terminal, connected to the chassis
#A55 #A55 - - -  
#A56 #A56 - - -  
#A57 #A57 - - -  
#A58 #A58 Signal ground, mass air flow (MAF) sensor U=Ulow -  
#A59 #A59 Power supply 5 V throttle unit, potentiometers 1 and 2 U =5 V -  
#A60 #A60 Signal ground
Air conditioning (A/C) pressure sensor, boost pressure sensor, engine coolant temperature (ECT) sensor, fuel pressure sensor, oil level sensor
U=Ulow -  
#A61 #B1 Signal (+), rear heated oxygen sensor (HO2S) U≈0.50 V Above 0.6 V or below 0.3 V  
#A62 #B2 Signal (-), rear heated oxygen sensor (HO2S) U=Ulow U=Ulow  
#A63 #B3 Signal ground U=Ulow - Ground terminal, connected to the chassis
#A64 #B4 Signal (-) front knock sensor (KS) U=Ulow -  
#A65 #B5 Camshaft position (CMP) sensor signal ground U=Ulow -  
#A66 #B6 Signal (-) flywheel sensor U=2.5 V U = sine wave voltage
Utop =5 V
Uoffset = 2.5 V
Measured to terminal #A48 (#A48)
The frequency increases with engine speed (RPM)
#A67 #B7 Signal (-) rear knock sensor (KS) U=Ulow -  
#A68 #B8 Signal air conditioning (A/C) pressure sensor U=0.9 V (at approximately 20°C) - U increases with pressure in the air conditioning (A/C) system
#A69 #B9 - - -  
#A70 #B10 - - -  
Control module terminal  Breakout box terminal  Signal type  Ignition on  Engine idling  Other 
#B1 #B11 Control modules communication cable (CAN L) - -  
#B2 #B12 - - -  
#B3 #B13 - - -  
#B4 #B14 Signal ground
clutch pedal sensor, outside temperature sensor
U=Ulow -  
#B5 #B15 Signal ground, accelerator pedal (AP) position sensor U=Ulow -  
#B6 #B16 - - -  
#B7 #B17 Control signal, leak diagnostic unit, pump Pump motor running: U=Ulow Pump motor not running: U = Ubat -  
#B8 #B18 Signal, coolant level sensor U=Ulow Low engine coolant level: U = Ubat
Normal engine coolant level: U = Ulow
 
#B9 #B19 Power supply, 5 V accelerator pedal (AP) position sensor U =5 V -  
#B10 #B20 - - -  
#B11 #B21 30-supply (Power supply from the battery) U = Ubat U = Ubat Ignition off: U = Ubat
#B12 #B22 - - -  
#B13 #B23 Control module communication cable (CAN H) - -  
#B14 #B24 - - -  
#B15 #B25 Clutch pedal sensor signal Unaffected: U=3.3 V
Fully depressed: 100mm U = 2.2 V
- U varies depending on the position of the clutch pedal
#B16 #B26 - - -  
#B17 #B27 Signal, accelerator pedal (AP) position sensor U = 0.4±0.1 V with unaffected accelerator pedal (AP)
U=2.5-4.4 V = the accelerator pedal (AP) fully depressed
On certain vehicles the accelerator pedal (AP) will be at the limit position before the signal reaches 4.4 V.
- U 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 At crank: U = Ubat
#B24 #B34 - - -  
#B25 #B35 Signal, accelerator pedal (AP) position sensor Utop =12 V
t = 4 ms
pulse ratio=8%±2% with unaffected accelerator pedal (AP) and 50% - 90% with fully depressed accelerator pedal (AP)
On certain vehicles the accelerator pedal (AP) will be at the limit before the signal reaches 90%.
- Pulse width modulation (PWM) signal from the accelerator pedal (AP) position sensor to the engine control module (ECM)
#B26 #B36 Stop lamp switch signal When the brake pedal is depressed: U = Ubat
When the brake pedal is not depressed U=Ulow
-  
#B27 #B37 - - -  
#B28 #B38 - - -  
#B29 #B39 Signal, outside temperature sensor (0° C) U=2.92 V
(+10° C) U=2.40V
(+20° C) U=1.90 V
(+30°C) U = 1.46 V
- Temperature range: -40 to +30°C
#B30 #B40 - - -  
#B31 #B41 - - -  
#B32 #B42 - - -  
#B33 #B43 - - -  
#B34 #B44 - - -  
#B35 #B45 - - -  
#B36 #B46 - - -  
#B37 #B47 Signal, ignition on, 15-supply U = Ubat U = Ubat Ignition off: U=Ulow
#B38 #B48 System relay control signal - 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, leak diagnostic unit, valve - - Valve activated: U = Ulow
Valve not activated: U = Ubat
#B41 #B51 - - -  
#B42 #B52 - - -  
#B43 #B53 - - -  
#B44 #B54 Control signal, air conditioning (A/C) relay - - Air conditioning (A/C) relay activated: U=Ulow
Air conditioning (A/C) relay not activated: U = Ubat
#B45 #B55 Fuel pump (FP) control signal, activation - - PWM signal to the central electronic module (CEM) to control the fuel pump (FP) relay
#B46 #B56 Malfunction indicator lamp (MIL) control signal U=Ulow Not activated U=Ubat
Activated: U=Ulow
 
#B47 #B57 Control signal, fuel pump (FP) control module - PWM signal pulse ratio 35% (+/-5%) engine at operating temperature PWM signal transmitted by the engine control module (ECM) to the fuel pump (FP) control module. The pulse ratio varies with the requested fuel pressure.
#B48 #B58 Control signal, engine cooling fan (FC), control modules - Not activated U=Ubat
Activated: U=Ulow
The engine cooling fan (FC) is controlled by the engine control module (ECM)
#B49 #B59 - - -  
#B50 #B60 - - -