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Home >> Volvo >> 2012 >> XC90 Base, FWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control - Signal Description And Specification >> Signal Specification, Engine Control Module (ECM) (B5254T2; 2005-2007) >> Signal Specification
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Signal Specification

General 

All values given below are between the terminals stated in column 2 (Control module terminal) 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)
CONNECTOR A

Breakout box terminal  Control module 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 =2.5V
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 Control signal ignition coil C, cylinder 4 U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A31 #A31 Control signal ignition coil B, cylinder 2 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 Sensor, power supply 5 V U =5 V   See the relevant wiring diagram for information about connected sensors
#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 = 2.5 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 =2.5V
Measured to terminal #A66 #B6)
The frequency increases with engine speed (RPM)
#A49 #A49 - - -  
#A50 #A50 Control signal ignition coil A, cylinder 1 U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A51 #A51 Control signal ignition coil E, cylinder 3 U=Ulow U=2.5 V
thigh =2 ms
The frequency varies according to engine speed (RPM)
#A52 #A52 Control signal ignition coil D, cylinder 5 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 Control modules communication cable (CAN L) - - -
#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 Sensor, signal ground U=Ulow - See the relevant wiring diagram for information about connected sensors
#B1 #A61 Signal (+), rear heated oxygen sensor (HO2S) U≈0.50 V Above 0.6 V or below 0.3 V  
#B2 #A62 Signal (-), rear heated oxygen sensor (HO2S) U=Ulow U=Ulow  
#B3 #A63 Signal ground U=Ulow - Ground terminal, connected to the chassis
#B4 #A64 Signal (-) front knock sensor (KS) U=Ulow -  
#B5 #A65 Camshaft position (CMP) sensor signal ground U=Ulow -  
#B6 #A66 Signal (-) flywheel sensor U=2.5 V U = sine wave voltage
Utop =5 V
Uoffset =2.5V
Measured to terminal #A48 (#A48)
The frequency increases with engine speed (RPM)
#B7 #A67 Signal (-) rear knock sensor (KS) U=Ulow -  
#B8 #A68 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
#B9 #A69 - - -  
#B10 #A70 - - -  
CONNECTOR B

Breakout box terminal  Control module terminal  Signal type  Ignition on  Engine idling  Other 
#B11 #B1 Control modules communication cable (CAN L) - - -
#B12 #B2 - - -  
#B13 #B3 - - -  
#B14 #B4 Sensor, signal ground U=Ulow - See the relevant wiring diagram for information about connected sensors
#B15 #B5 Signal ground, accelerator pedal (AP) position sensor U=Ulow -  
#B16 #B6 - - -  
#B17 #B7 Control signal, leak diagnostic unit, pump Pump motor running: U=Ulow Pump motor not running: U = Ubat -  
#B18 #B8 Signal, coolant level sensor U=Ulow Low engine coolant level: U = Ubat
Normal engine coolant level: U = Ulow
 
#B19 #B9 Power supply, 5 V accelerator pedal (AP) position sensor U =5 V -  
#B20 #B10 - - -  
#B21 #B11 30-supply (Power supply from the battery) U=Ubat U=Ubat Ignition off: U = Ubat
#B22 #B12 - - -  
#B23 #B13 Control module communication cable (CAN H) - -  
#B24 #B14 - - -  
#B25 #B15 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
#B26 #B16 - - -  
#B27 #B17 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)
#B28 #B18 - - -  
#B29 #B19 - - -  
#B30 #B20 - - -  
#B31 #B21 - - -  
#B32 #B22 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)
#B33 #B23 Signal crank, 50-supply U=Ulow U=Ulow At crank: U = Ubat
#B34 #B24 - - -  
#B35 #B25 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)
#B36 #B26 Stop lamp switch signal When the brake pedal is depressed: U = Ubat
When the brake pedal is not depressed U=Ulow
-  
#B37 #B27 - - -  
#B38 #B28 - - -  
#B39 #B29 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
#B40 #B30 - - -  
#B41 #B31 - - -  
#B42 #B32 - - -  
#B43 #B33 - - -  
#B44 #B34 Control signal, leak diagnostic unit, heater pad   - Heating element activated: U = Ulow Heater pad not activated: U = Ubat
#B45 #B35 - - -  
#B46 #B36 - - -  
#B47 #B37 Signal, ignition on, 15-supply U=Ubat U=Ubat Ignition off: U=Ulow
#B48 #B38 System relay control signal - U=Ulow Relay activated: U=Ulow
Relay not activated: U = Ubat
The system relay runs on (2-5 minutes)
#B49 #B39 - - -  
#B50 #B40 Control signal, leak diagnostic unit, valve - - Valve activated: U = Ulow
Valve not activated: U = Ubat
#B51 #B41 - - -  
#B52 #B42 - - -  
#B53 #B43 - - -  
#B54 #B44 Control signal, air conditioning (A/C) relay - - Air conditioning (A/C) relay activated: U=Ulow
Air conditioning (A/C) relay not activated: U = Ubat
#B55 #B45   - -  
#B56 #B46 Malfunction indicator lamp (MIL) control signal U=Ulow Not activated U=Ubat
Activated: U=Ulow
 
#B57 #B47 Control signal, fuel pump (FP) control module - PWM signal pulse ratio 35% (+/-5%) engine at operating temperature Pulse width modulation (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.
#B58 #B48 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).
#B59 #B49 - - -  
#B60 #B50 - - -