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Home >> Volvo >> 1998 >> C70 2D Convertible, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Fuel, Ignition And Engine Control Systems - Specifications, Electrical/Electronic (Convertible) >> Signal Specification, Engine Control Module (ECM) (B5244S; 2000) >> Signal specification
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Signal specification

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 #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, (terminal #B1). Example: #A61 (#B1). 

U= DC voltage in volts (V) U A/C = AC voltage in volts (V)
U bat = Battery voltage in volts (V) f = Frequency in Hertz (Hz)
U low = Voltage near 0 V or 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 - 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 = 2.90 V
(+20 C) U = 2.38 V
(+30 C) U = 1.89 V
-
#A5 (#A5) Control signal
engine cooling fan (FC) high-speed
Engine cooling fan (FC) off U = Ubat
Engine cooling fan (FC) on U = Ulow
- -
#A6 (#A6) Control signal
engine cooling fan (FC) low-speed
Engine cooling fan (FC) off U = Ubat
Engine cooling fan (FC) on U = Ulow
- -
#A7 (#A7) - - - -
#A8 (#A8) - - - -
#A9 (#A9) - - - -
#A10 (#A10) - - - -
#A11 (#A11) Control signal
preheating rear heated oxygen sensor (HO2S)
U = Ubat Preheating off U = Ubat
Preheating U = Ulow
-
#A12 (#A12) - - - -
#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 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 (+)
transmission input speed sensor
U=2.5 V
U = Ulow
U = sine wave voltage -
#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, 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 volt - -
#A58 (#A58) Power supply, manifold absolute pressure (MAP) sensor
A/C pressure sensor
U=5 volt - -
#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
transmission input speed sensor
U = Ulow - -
#A67 (#B7) - - - -
#A68 (#B8) - - - -
#A69 (#B9) Control signal
preheating front 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 CAN driver module
#B2 (#B12) - - - -
#B3 (#B13) - - - -
#B4 (#B14) Signal ground
intake air temperature (IAT) 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 volt - -
#B10 (#B20) Power supply
fuel tank pressure sensor
U=5 volt - -
#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 CAN driver module
#B14 (#B24) - - - -
#B15 (#B25) Signal
clutch pedal sensor
U=3.3 volts (unaffected)
U=2.2 volts (fully
depressed, 100 mm)
- Varies depending on the position of the clutch pedal
#B16 (#B26) Signal
brake sensor
U=3.1 volts (unaffected)
U=2.6 volts (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 volts (idling)
U=4.4 volt (wide open throttle (WOT))
- Varies depending on the position of the accelerator pedal (AP)
#B18 (#B28) - - - -
#B19 (#B29) Signal (+)
cruise control SET+
- - -
#B20 (#B30) Signal (+)
cruise control RESUME
- - -
#B21 (#B31) Output signal (+)
engine speed
U = Ulow U = quadratic wave voltage
Utop = Ubat
frequency increases with engine speed (RPM)
#B22 (#B32) Immobilizer communication cable (also data link connector (DLC) communication link) No communication on the cable: U=90% of Ubat .
During communication: Data communication, pulsed signal between Ubat and 0 V
Other values apply if a generic fault-tracing instrument is connected to the data link connector (DLC). The engine control module (ECM) and immobilizer control module communicate with each other for 2 seconds after the ignition is switched on to determine whether engine start should be permitted. After this time, the immobilizer control module changes internally so that the cable is connected to the communication port in the data link connector (DLC) (terminal #7).
#B23 (#B33) Signal (+)
crank, +50 supply
U = Ulow U = Ulow U = Ubat at crank
#B24 (#B34) - - - -
#B25 (#B35) Signal (+)
accelerator pedal (AP) position sensor, 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) Output signal
Engine coolant temperature (ECT) to the air conditioning (A/C) system
Utop = Ubat
t = 4 ms
pulse ratio = varies with engine coolant temperature (ECT)
- -
#B28 (#B38) - - - -
#B29 (#B39) Signal
outside temperature sensor
(0°C) U=2.34 V
(+10°C) U=1.82 V
(+20°C) U=1.38 V
(+25°C) U=1.19 V
(+30°C) U=1.03 V
- Temperature range: -40°C to +110°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) Signal A/C request U = Ubat on request, otherwise U = Ulow - -
#B33 (#B43) Signal cruise control on/off See terminal #B47 - -
#B34 (#B44) Signal cruise control SET- See terminal #B47 - -
#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: Ulow
Relay not activated: Ubat
The system relay runs on (2-15 minutes)
#B39 (#B49) - - - -
#B40 (#B50) Control signal
EVAP canister shut-off valve
U=3.82 V - -
#B41 (#B51) Control signal
Electronic throttle system (ETS) warning lamp
U = Ulow U = Ubat (not activated)
U = Ulow (activated)
-
#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
- - -
#B46 (#B56) Control signal
malfunction indicator lamp (MIL)
U = Ulow U = Ubat (not activated)
U = Ulow (activated)
-
#B47 (#B57) Power supply
Cruise control
U = Ubat (not activated)
U = pulse train
Utop = Ubat
t = 20 ms
thigh = 0.5 ms
- -
#B48 (#B58) Control signal
engine start inhibiting
U = Ulow (activated)
U = Uhigh (not activated)
- In certain markets, the engine can only be started with the clutch pedal depressed (U = Ulow)
#B49 (#B59) - - - -
#B50 (#B60) - - - -