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Home >> Volvo >> 2012 >> XC90 R-Design, FWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control - Signal Description And Specification >> Signal Specifications, Engine Control Module (ECM) (B6294T; 2003-2004) >> Signal Specification
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Signal Specification

General 

All values listed below should be measured between the respective terminal in column 1 (control module terminal) and terminal #B3 unless stated otherwise in column 6 (Other). 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 - - -  
#A3 #A3 - - -  
#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 =1.2V
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 - PWM signal Utop =U bat
f=250Hz (±12.5 Hz)
Pulse ratio 20-95%
The pulse ratio governs control of the camshaft
#A14 #A14 Injector no. 6 control signal U = Ubat t= 2-3 ms t increases with engine speed (RPM) and load
#A15 #A15 Injector no. 2 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 - Measured via the system relay
#A18 #A18 Control signal, preheating, bank 1, front heated oxygen sensor (HO2S) 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), bank 1, pump current - - Pulsed current supply, not measured
#A25 #A25 Front heated oxygen sensor (HO2S), bank 2, pump current - - Pulsed current supply, not measured
#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=2.5V
The frequency varies according to engine speed (RPM)
#A28 #A28 Front heated oxygen sensor (HO2S), bank 1, calibration current - - Not measured
#A29 #A29 Power supply, 5 V camshaft position (CMP) sensor U =5 V -  
#A30 #A30 Ignition coil no. 5 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 Injector no. 4 control signal U = Ubat tlow =2-3 ms t increases with engine speed (RPM) and load
#A33 #A33 Injector no. 3 control signal U = Ubat tlow =2-3 ms t increases with engine speed (RPM) and load
#A34 #A34 Injector no. 5 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 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 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
U =5 V -  
#A40 #A40 - - -  
#A41 #A41 Signal (+), front heated oxygen sensor (HO2S)
bank 1
- - Pulsed current signal, not measured
#A42 #A42 Signal (-), front heated oxygen sensor (HO2S)
bank 1
- - Pulsed current signal, not measured
#A43 #A43 Signal (+), front heated oxygen sensor (HO2S)
bank 2
- - Pulsed current signal, not measured
#A44 #A44 Signal (-), front heated oxygen sensor (HO2S)
bank 2
- - Pulsed current signal, not measured
#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 = 2.5 V
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 Ignition coil no. 4 control signal U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A50 #A50 Ignition coil no. 2 control signal U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A51 #A51 Ignition coil no. 6 control signal U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A52 #A52 Ignition coil no. 3 control signal U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A53 #A53 Power ground 3 U low - Ground terminal
connected to the chassis
#A54 #A54 Power ground 2 U low - 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
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 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 Air conditioning (A/C) pressure sensor signal U=0.9 V (at 20°C) - U increases with pressure in the air conditioning (A/C) system
#A69 #B9 Front heated oxygen sensor (HO2S), bank 2, calibration current - - Not measured
#A70 #B10 Control signal, preheating, bank 2, front heated oxygen sensor (HO2S) U = Ubat Preheating off: U = Ubat
Preheating on: U=Ulow
 
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 position 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: 100 mm U=2.2 V
- U varies depending on the position of the clutch pedal
#B16 #B26 - - -  
#B17 #B27 Signal, accelerator pedal (AP) position sensor Unaffected: U≈0.4 V
Fully depressed accelerator pedal (AP): U≈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 Pulse width modulation (PWM) signal
Utop =Ubat
t=5 ms
pulse ratio = 8-88%
- 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) activation control signal - - Pulse width modulated (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 - - -  
#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 - - -