Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2009 Volvo XC70 BaseFACTORY OEM SERVICE PROCEDURE
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 | Rear heated oxygen sensor (HO2S), 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 | Front heated oxygen sensor (HO2S), bank 2, signal (+) | - | λ = when current is 0 mA | Measurement range: 0 ± 12 mA. Negative current indicates a rich fuel/air mixture. |
| #A32 | #A32 | Front heated oxygen sensor (HO2S), bank 2, signal (-) | - | λ = when current is 0 mA | Measurement range: 0 ± 12 mA. Negative current indicates a rich fuel/air mixture. |
| #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 | Rear heated oxygen sensor (HO2S), bank 1, signal (+) | - | λ = 1 at approx. 700 mV λ >1 at approx. 200 mV |
|
| #A41 | #A41 | Rear heated oxygen sensor (HO2S), bank 2, 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 (HO2S) bank 2, 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 | Front heated oxygen sensor (HO2S) bank 2 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 | Rear heated oxygen sensor preheating bank 1, control signal | - | Utop
= 12 V Pulse ratio 30 - 60 % |
|
| #B29 | #A89 | Rear heated oxygen sensor preheating bank 2, control signal | - | Utop
= 12 V Pulse ratio 30 - 60 % |
|
| #B30 | #A90 | Cam profile solenoid 1, control signal | U = Ubat | U = Ubat | |
| #B31 | #A91 | Cam profile solenoid 2, control signal | U = Ubat | U = Ubat | |
| #B32 | #A92 | LIN signal, Generator (GEN) | |||
| #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=2.40V (+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 |
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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