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Home >> Volvo >> 2009 >> XC70 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control Module (ECM) - Specifications, Electrical/Electronic >> Signal Specification, Engine Control Module (ECM) (B6324S2; 2010) >> Signal Specification
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Signal Specification

All values below are measured between the relevant terminal in column 2 and #Axx (#Axx on the breakout box) unless otherwise stated in parenthesis after the table entry.

Connector A (96-pin) corresponds to terminals #A1 - #B36 on the breakout box.

Connector B (58-pin engine side) corresponds to terminals #C1 - #58 on the breakout box.

NOTE:

Connect the breakout box and check the ground connections before starting to measure.

CONNECTOR A

Breakout box terminal  Control module terminal  Signal type  Ignition on  Engine idling  Miscellaneous 
#A1 #A1 - - -  
#A2 #A2 - - -  
#A3 #A3 - - -  
#A4 #A4 - - -  
#A5 #A5 - - -  
#A6 #A6 Impulse sensor, signal (-) U=Ulow   Measured to terminal #A30 (#A30).
#A7 #A7 Camshaft sensor intake, ground U=Ulow U=Ulow  
#A8 #A8 Camshaft sensor exhaust, ground U=Ulow U=Ulow  
#A9 #A9 Front heated oxygen sensor (HO2S), bank 1, signal (+) - λ = 1 when current is 0 mA Measurement range: 0 ± 12 mA.
Negative current indicates a rich fuel/air mixture.
#A10 #A10 Front heated oxygen sensor (HO2S), bank 1, signal (-) - λ = 1 when current is 0 mA Measurement range: 0 ± 12 mA.
Negative current indicates a rich fuel/air mixture.
#A11 #A11 Camshaft sensor intake, supply voltage U =5 V U =5 V  
#A12 #A12 Camshaft sensor exhaust, supply voltage U =5 V U =5 V  
#A13 #A13 Engine coolant temperature (ECT) sensor, signal (+30 °C) U=1.22 V (+80 °C)
U=0.29 V
(+100 °C) U=0.17 V
(+30 °C) U=1.22 V
(+80 °C) U=0.29 V
(+100 °C) U=0.17 V
U drops with increased engine coolant temperature.
#A14 #A14 Mass air flow (MAF) sensor, signal ground U=Ulow U=Ulow  
#A15 #A15        
#A16 #A16        
#A17 #A17 Electronic throttle module (ETA), ground U=Ulow U=Ulow  
#A18 #A18 Middle heated oxygen sensor bank 1, signal (-).      
#A19 #A19 Knock sensor (KS) bank 1, signal (-) U=Ulow    
#A20 #A20 Knock sensor (KS) bank 2, signal (-) U=Ulow    
#A21 #A21 Fuel temperature/fuel pressure sensor, ground U=Ulow U=Ulow  
#A22 #A22 Mass air flow (MAF) sensor, signal ground U=Ulow U=Ulow  
#A23 #A23 Manifold absolute pressure (MAP) sensor, ground U=Ulow U=Ulow  
#A24 #A24 Manifold absolute pressure (MAP) sensor, supply voltage U =5 V    
#A25 #A25        
#A26 #A26        
#A27 #A27        
#A28 #A28        
#A29 #A29        
#A30 #A30 Impulse sensor, signal (+) U=Ulow U=sinus voltage
U≈1.7 to 1.9 V
Measured to terminal #A6 (#A6). The voltage increases with increased engine speed (rpm).
#A31 #A31        
#A32 #A32        
#A33 #A33 Exhaust camshaft position (CMP) sensor, signal U = 5 V or Ulow U= Pulsed signal
Umax. >4.5 V
Umin. <1 V
Measure against #A8 (#A8). The frequency varies with engine rpm. Measure with advanced measuring tool.
#A34 #A34 Intake camshaft position (CMP) sensor, signal U = 5 V or Ulow U= Pulsed signal
Umax. >4.5 V
Umin. <1 V
Measure against #A7 (#A7). The frequency varies with engine rpm. Measure with advanced measuring tool.
#A35 #A35 - - -  
#A36 #A36 - - -  
#A37 #A37 - - -  
#A38 #A38 Actuator variable intake upper, control signal - -  
#A39 #A39 Actuator variable intake lower, control signal - -  
#A40 #A40 Middle heated oxygen sensor bank 1, signal (+). - λ = 1 at approx. 700 mV
λ >1 at approx. 200 mV
 
#A41 #A41 Rear heated oxygen sensor (HO2S), bank 1, signal (+) - λ = 1 at approx. 700 mV
λ >1 at approx. 200 mV
 
#A42 #A42 Knock sensor (KS) bank 1, signal (+) U=2.5 V   Measured to terminal #A19 (#A19).
#A43 #A43 Knock sensor (KS) bank 2, signal (+) U=2.5 V   Measured to terminal #A20 (#A20).
#A44 #A44 -      
#A45 #A45 Rear heated oxygen sensor bank 1, ground U=Ulow U=Ulow  
#A46 #A46 Fuel temperature sensor, signal     Measurement range: -40 to +130 °C.
#A47 #A47 Fuel temperature/fuel pressure sensor, supply voltage U =5 V    
#A48 #A48 Electronic throttle module (ETA), voltage feed U =5 V U =5 V  
#A49 #A49        
#A50 #A50 -      
#A51 #A51 -      
#A52 #A52 -      
#A53 #A53 -      
#A54 #A54        
#A55 #A55        
#A56 #A56 Ignition coil cyl 4, control signal U=Ulow Utop = 12 V pulse ratio 30% f=240 Hz Pulse ratio and frequency increases with increased engine speed (rpm)
#A57 #A57 Ignition coil cyl 2, control signal U=Ulow Utop = 12 V pulse ratio 30% f=240 Hz Pulse ratio and frequency increases with increased engine speed (rpm)
#A58 #A58 Ignition coil cyl 6, control signal U=Ulow Utop = 12 V pulse ratio 30% f=240 Hz Pulse ratio and frequency increases with increased engine speed (rpm)
#A59 #A59 Ignition coil cyl 3, control signal U=Ulow Utop = 12 V pulse ratio 30% f=240 Hz Pulse ratio and frequency increases with increased engine speed (rpm)
#A60 #A60 Ignition coil cyl 5, control signal U=Ulow Utop = 12 V pulse ratio 30% f=240 Hz Pulse ratio and frequency increases with increased engine speed (rpm)
#B1 #A61 Ignition coil cyl 1, control signal U=Ulow Utop = 12 V pulse ratio 30% f=240 Hz Pulse ratio and frequency increases with increased engine speed (rpm)
#B2 #A62 Misfire signal     Pulse width modulation (PWM) signal, for ignition coil cyl. 1, 4, 6 and 7
#B3 #A63 Oil level and oil temperature sensor, signal     Pulse width modulation (PWM) signal
#B4 #A64        
#B5 #A65 Electronic throttle module (ETA), throttle position sensor circuit 1, signal Unaffected: U≈0.8 V
Fully depressed accelerator pedal: U≈4 V
  Voltage varies depending on the position of the throttle. Voltage increases with increased throttle opening.
#B6 #A66 Intake air temperature (IAT) sensor signal (+20 °C) U=3.50 V
(+30 °C) U=3.00 V
(+40 °C) U=2.50 V
(+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 mass air flow (MAF) sensor.
#B7 #A67 Electronic throttle module (ETA), throttle position sensor circuit 2, signal Unaffected: U≈1.7 V
Fully depressed accelerator pedal: U≈4.1 V
  Voltage varies depending on the position of the throttle. Voltage increases with increased throttle opening.
#B8 #A68 Engine coolant temperature (ECT) sensor, signal (+30 °C) U=1.22 V (+80 °C)
U=0.29 V
(+100 °C) U=0.17 V
(+30 °C) U=1.22 V
(+80 °C) U=0.29 V
(+100 °C) U=0.17 V
U drops with increased engine coolant temperature.
#B9 #A69 Manifold absolute pressure (MAP) sensor, signal U≈3.7 V at 1000 mbar    
#B10 #A70 Mass air flow sensor, signal U≈0.6 V U≈1.4 V U increases with increasing air mass
#B11 #A71 Fuel pressure sensor, signal      
#B12 #A72        
#B13 #A73 Power supply from system relay U = Ubat U = Ubat  
#B14 #A74 Electronic Throttle Module (ETA) engine, control signal (-) Idle = -1.5
Wide open throttle (WOT) = 2
Pulse width modulation (PWM) signal.
Utop =Ubat
Pulse ratio 0-100%
The polarity of the control signal switches when the damper motor is to be deployed in the opposite direction.
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 #A75.
#B15 #A75 Electronic Throttle Module (ETA) engine, control signal (+) Idle = -1.5
Wide open throttle (WOT) = 2
Pulse width modulation (PWM) signal.
Utop =Ubat
Pulse ratio 0-100%
The polarity of the control signal switches when the damper motor is to be deployed in the opposite direction.
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 #A74.
#B16 #A76 Front heated oxygen sensor (HO2S) bank 1 preheating, control signal   Utop = 12 V pulse ratio 30 - 60 % f=8 Hz Pulsed 12 V-signal.
#B17 #A77 Middle heated oxygen sensor bank 1 preheating, control signal   Utop = 12 V pulse ratio 30 - 60 % f=8 Hz Pulsed 12 V-signal.
#B18 #A78 Injector 1, control signal U = Ubat t = 2-3 ms t increases with engine speed and load
#B19 #A79 Injector 5, control signal U = Ubat t = 2-3 ms t increases with engine speed and load
#B20 #A80 Injector 3, control signal U = Ubat t = 2-3 ms t increases with engine speed and load
#B21 #A81 Injector 6, control signal U = Ubat t = 2-3 ms t increases with engine speed and load
#B22 #A82 Injector 2, control signal U = Ubat t = 2-3 ms t increases with engine speed and load
#B23 #A83 Injector 4, control signal U = Ubat t = 2-3 ms t increases with engine speed and load
#B24 #A84 Evaporative emission system (EVAP) valve, control signal (signal ground) U = Ubat   Pulse width modulation (PWM) signal during opening (control) of the evaporative emission system (EVAP) valve. The pulse ratio varies with regulating.
#B25 #A85 Variable A/C compressor, control signal   Utop = 12 V pulse ratio 30 - 75 % f=400 Hz Pulsed 12 V-signal.
#B26 #A86 Reset valve camshaft intake (VVT), control signal - Pulse width modulation (PWM) signal
Utop =Ubat
f=300 Hz
Pulse ratio 5%
The pulse ratio varies during regulation.
#B27 #A87        
#B28 #A88        
#B29 #A89 Rear heated oxygen sensor preheating bank 1, control signal - Utop = 12 V
Pulse ratio 30 - 60 %
 
#B30 #A90        
#B31 #A91        
#B32 #A92 LIN signal, alternator, radiator temperature sensor      
#B33 #A93 -      
#B34 #A94 -      
#B35 #A95        
#B36 #A96 -      
           
CONNECTOR B

Breakout box terminal  Control module terminal  Signal type  Ignition on  Engine idling  Miscellaneous 
#C1 #B1        
#C2 #B2 Power ground U=Ulow   Ground terminal connected to chassis.
#C3 #B3 Power supply from system relay U = Ubat U = Ubat  
#C4 #B4 Power ground U = Ubat   Ground terminal connected to chassis.
#C5 #B5 Power supply from system relay U = Ubat U = Ubat  
#C6 #B6 Power ground U = Ubat   Ground terminal connected to chassis.
#C7 #B7 - - - -
#C8 #B8 Cooling fan control module, control signal     Pulse width modulation (PWM) signal to engine cooling fan (FC) control module
#C9 #B9 Start relay, signal (-)      
#C10 #B10 Air conditioning (A/C) relay, control signal (signal ground) - -  
#C11 #B11 Starter relay, control signal (+)      
#C12 #B12        
#C13 #B13  
Automatic: transmission control module (TCM), gear position signal. Manual: clutch pedal switch
With P/N connected: U=Ulow
With P/N disconnected U=Ubat
  Grounded in the transmission control module (TCM) when in P/N.
#C14 #B14 Power supply (wake up, 15-feed U = Ubat U = Ubat  
#C15 #B15 Start, signal 50-feed U = Ubat U = Ubat Ignition off: U=Ulow
#C16 #B16 Supply from B+      
#C17 #B17 Start, signal 50-feed   U=Ubat at crank The engine control module (ECM) requests engine starting via the central electronic module (CEM).
#C18 #B18 - - - -
#C19 #B19     -  
#C20 #B20        
#C21 #B21 Fuel pump (FP) control module, control signal - - Pulse width modulated (PWM) signal to the central electronic module (CEM) to control the fuel pump (FP) relay.
#C22 #B22 - - - -
#C23 #B23        
#C24 #B24 - -   -
#C25 #B25 - - - -
#C26 #B26 Accelerator pedal (AP) position sensor, PWM signal PWM signal Utop =Ubat t=5 ms pulse ratio 8 - 88 % Pulse width modulation (PWM) signal Utop =Ubat t=5 ms pulse ratio 6-14% The PWM signal from the accelerator pedal (AP) position sensor to the engine control module (ECM). The pulse ratio increases as the accelerator pedal (AP) is depressed.
#C27 #B27 System relay, control signal   U=Ulow Engine control module (ECM) grounds with ignition on and releases after run.
#C28 #B28        
#C29 #B29        
#C30 #B30 Brake light switch      
#C31 #B31 A/C high pressure sensor, power supply U =5 V - -
#C32 #B32 - - - -
#C33 #B33        
#C34 #B34 Outside temperature sensor, ground U=Ulow - -
#C35 #B35 Outside temperature sensor, Signal (0 °C) U=2.92 V
(+10 °C) U=2.40 V
(+20 °C) U=1.90 V (+30 °C)
U =1.46 V
  Temperature range: -40 to +30 °C
ref: 2.87 V at 21 °C
#C36 #B36 - - - -
#C37 #B37 - - - -
#C38 #B38 - - - -
#C39 #B39 - - - -
#C40 #B40 - - - -
#C41 #B41 Communication lead, control modules (CAN L)      
#C42 #B42 - - - -
#C43 #B43 - - - -
#C44 #B44 - - - -
#C45 #B45 Leak diagnostic unit, preheating, control signal     Heating element activated: U=Ulow
Heating element not activated: U=Ubat
Certain markets only.
#C46 #B46 Leak diagnostic unit valve, control signal     Valve activated: U=Ulow
Valve not activated: U=Ubat
Certain markets only.
#C47 #B47 - - - -
#C48 #B48        
#C49 #B49        
#C50 #B50 - - - -
#C51 #B51 A/C high pressure sensor, signal   U=1.4 V The voltage increases with increased pressure.
#C52 #B52 - - - -
#C53 #B53 A/C high pressure sensor, ground U=Ulow    
#C54 #B54 Communication cable control module (CAN H)      
#C55 #B55 -   - -
#C56 #B56 - -   -
#C57 #B57 - - - -
#C58 #B58