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Home >> Volvo >> 2009 >> V70 >> Repair and Diagnosis (Single Page) >> Electrical >> Motors, Switches, Relays >> Central Electronic Module (CEM) And Accessory USB Unit (AUU) - Specifications, Electrical/Electronic >> Signal Description, Central Electronic Module (CEM) (Late Version, Generation 2) (2010) >> Signal Description Central Electronic Module (CEM)
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Signal Description Central Electronic Module (CEM)

All values given below are between the terminals stated in column 1 and terminal #D5 (power ground). This applies unless otherwise indicated in the last column.

NOTE: It is important to connect the breakout box and check the ground connections before starting to measure.
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 t = Time in seconds
PWM = Pulse-width modulated signal in % - -
Fig 1: Identifying 76-Pin Connector
GLL155449Courtesy of VOLVO CARS CORPORATION
SIGNAL TABLE

Connector C1 (Green)
Breakout box terminal  Control module terminal  Signal type  Ignition off 
Active/Not active 
Ignition on 
Active/Not active 
Miscellaneous 
#A1 #C1:1 Reserve - - -
#A2 #C1:2 Reserve - - -
#A3 #C1:3 Collision signal, output signal Ulow Ubat/ /Ulow Collision signal to Engine control module (ECM)
#A4 #C1:4 Front left-hand turn signal lamp, power supply Ulow Ubat -Ulow /Ulow Flashing hazard lights also work with ignition off.
#A5 #C1:5 Brake light switch, input signal Ubat /Ulow Ubat/ /Ulow Signal to Engine control module (ECM)
#A6 #C1:6 Engine control module (ECM), waking Ulow Ubat /Ulow -
#A7 #C1:7 Reserve - - -
#A8 #C1:8 Auxiliary light relay, control signal U = 0 V U=Ubat /U=0 V Extra accessory
#A9 #C1:9 Comfort relay, control signal Ubat Ulow /Ubat -
#A10 #C1:10 Headlamp cleaning, control signal Ubat Ulow /Ubat -
#A11 #C1:11 Relay, horn, control signal Ulow /Ubat Ulow /Ubat -
#A12 #C1:12 Electronic power steering module, control signal Ubat with ignition off
Frequency signal otherwise
-
#A13 #C1:13 Relay 15-feed, control signal Ubat ulow Electric distribution box, engine compartment
#A14 #C1:14 Reserve - - -
#A15 #C1:15 Running light right front, side running light right, voltage feed Ubat /Ulow Ubat /Ulow For S60/V60/XC60 also right LED-light in the front.
#A16 #C1:16 Clutch pedal sensor, external, voltage supply Ulow U = 5 V -
#A17 #C1:17 Reserve - - -
#A18 #C1:18 Running light left front, side running light left, voltage feed Ubat /Ulow Ubat /Ulow For S60/V60/XC60 also left LED-light in the front.
#A19 #C1:19 Left headlamp control unit (LHCU), LIN communication The voltage is 0 V - Ubat during communication Spare on vehicles before model year 2012
#A20 #C1:20 Right headlamp control unit (RHCU), LIN communication The voltage is 0 V - Ubat during communication Spare on vehicles before model year 2012
#A21 #C1:21 Reserve - - -
#A22 #C1:22 Reserve - - -
#A23 #C1:23 Reserve - - -
#A24 #C1:24 Reserve - - -
#A25 #C1:25 Reserve - - -
#A26 #C1:26 Reserve - - -
#A27 #C1:27 Reserve - - -
#A28 #C1:28 Washer fluid level, switch Ulow at normal level
Ubat at level below 1 litre
-
#A29 #C1:29 Reversing switch, input signal - - Only manual
#A30 #C1:30 Communication CAN_H, Average speed network During communication the voltage is 2.0 - 3.5 V MS-CAN
#A31 #C1:31 Communication CAN_L, Average speed network During communication the voltage is 1.5 - 2.5 V MS-CAN
#A32 #C1:32 Reserve - - -
#A33 #C1:33 Reserve - - -
#A34 #C1:34 Clutch pedal sensor, external, input signal - 0-5 V -
#A35 #C1:35 Front axle sensor, control signal Ulow /Ulow U = 0-5V with ignition on Spare on vehicles before model year 2012
#A36 #C1:36 Sensor front axle and rear axle, power supply Ulow /Ulow Ubat with ignition on Spare on vehicles before model year 2012
#A37 #C1:37 Reserve - - -
#A38 #C1:38 Reserve - - -
#A39 #C1:39 Engine hood, switch Ulow with the hood closed
Ulow -Ubat with the hood open
Pulsed signal, f = 100 Hz
#A40 #C1:40 Brake fluid level, switch Ulow at normal level
Ubat at low level
-
#A41 #C1:41 Start button 1, output signal Ubat /Ulow Ubat /Ulow Connection of #C3-3 to Engine control module (ECM).
#A42 #C1:42 Coolant level sensor, switch Ulow at normal level
Ubat at low level
-
#A43 #C1:43 Reserve - - -
#A44 #C1:44 Reserve -    
#A45 #C1:45 Reserve - - -
#A46 #C1:46 Reserve - - -
#A47 #C1:47 Communication LIN bus 2 During communication the voltage is 0 V - Ubat Siren control module (SCM)
#A48 #C1:48 Communication LIN bus 8 During communication the voltage is 0 V - Ubat Wiper motor module (WMM)
#A49 #C1:49 Communication LIN bus 8 During communication the voltage is 0 V - Ubat Battery Monitoring Module (BMS)
#A50 #C1:50 Reserve - - -
#A51 #C1:51 Reserve - - -
#A52 #C1:52 Clutch pedal sensor, external, ground Ulow Ulow -
#A53 #C1:53 Front axle sensor, ground Ulow /Ulow Ulow /Ulow Spare on vehicles before model year 2012
#A54 #C1:54 Electronic ground U = Ulow U = Ulow -
#A55 #C1:55 Left high beam, power supply Ubat /Ulow Ubat /Ulow -
#A56 #C1:56 Reserve - - -
#A57 #C1:57 Reserve - - -
#A58 #C1:58 Reserve - - -
#A59 #C1:59 Reserve - - -
#A60 #C1:60 Siren (SCM), voltage feed Ubat Ubat -
#B1 #C1:61 Reserve - - -
#B2 #C1:62 Reserve - - -
#B3 #C1:63 Relay 15-feed, voltage feed Ulow Ubat Electric distribution box, engine compartment
#B4 #C1:64 Right low beam, power supply Ulow Ubat /Ulow -
#B5 #C1:65 Rear washer motor, voltage feed Ulow Ubat /Ulow -
#B6 #C1:66 Front right-hand turn signal lamp, power supply Ulow Ubat -Ulow /Ulow Flashing hazard lights also work with ignition off.
#B7 #C1:67 Reserve - - -
#B8 #C1:68 Reserve - - -
#B9 #C1:69 Reserve - - -
#B10 #C1:70 Reserve - - -
#B11 #C1:71 Front left fog lamp, power supply Ulow Ubat /Ulow Spare on S60/V60
#B12 #C1:72 Front right fog lamp, power supply Ulow Ubat /Ulow Spare on S60/V60
#B13 #C1:73 Right high beam, power supply Ubat /Ulow Ubat /Ulow -
#B14 #C1:74 Forward looking radar (FLR), 15-voltage feed Ulow Ubat -
#B15 #C1:75 Left low beam, power supply Ulow Ubat /Ulow -
#B16 #C1:76 Front washer motor, power supply Ulow Ubat /Ulow -
Fig 2: Identifying 76-Pin Connector
GLL155449Courtesy of VOLVO CARS CORPORATION
Connector C2 (Brown)
Breakout box terminal  Control module terminal  Signal type  Ignition off 
Active/Not active 
Ignition on 
Active/Not active 
Miscellaneous 
#C1 #C2:1 Reserve - - -
#C2 #C2:2 Rear window defroster, control signal Ubat Ulow /Ubat -
#C3 #C2:3 Foldable head restraint Ubat Ulow /Ubat -
#C4 #C2:4 Rear wiper motor, control signal - Ulow /Ubat -
#C5 #C2:5 Relay 15-feed, control signal Ubat Ulow Electric distribution box in luggage compartment
#C6 #C2:6 Parking brake switch - Ulow /Ubat Not on vehicles with electric parking brake (EPB)
#C7 #C2:7 Communication LIN bus 2 During communication the voltage is 0 V - Ubat Heart beat sensor (HBS) and mass movement sensor (MMS). (Mass movement sensor only for XC60 with panorama roof.) (Heart beat sensor only fr vehicles before model year 2011.)
#C8 #C2:8 Communication LIN bus 0 During communication the voltage is 0 V - Ubat -
#C9 #C2:9 Central high level brake light, power supply Ubat /Ulow Ubat /Ulow Only station wagon
#C10 #C2:10 Lock motor central lock rear door left, switch Ubat if door open
Ulow in others
Door switch
#C11 #C2:11 Lock motor central lock front door left, switch Ubat if door open
Ulow in others
Door switch
#C12 #C2:12 Reserve - - -
#C13 #C2:13 Reserve - - -
#C14 #C2:14 Reserve - - -
#C15 #C2:15 Fuel level sensor, ejector side Ulow U = 0.5-4 V Pulsed signal (PWM), f = 5 Hz (f = 1 Hz for flexifuel vehicles),
#C16 #C2:16 Accelerator pedal (AP) position sensor, power supply Ulow U = 5 V -
#C17 #C2:17 Voltage secondary battery Ubat Ubat Only on vehicles with the function "Automatic engine start/stop".
The voltage may differ from the vehicle's other voltage. First when the secondary battery is connected to the vehicle's electrical system (secondary battery relay activated) when, e. g., charging the battery, the voltage is the same as for other voltage in the vehicle.
#C18 #C2:18 Reserve - - -
#C19 #C2:19 Reserve - - -
#C20 #C2:20 Reserve - - -
#C21 #C2:21 Reserve - - -
#C22 #C2:22 Reserve - - -
#C23 #C2:23 Seat belt reminder sensor, passenger seat - Ulow /Ubat -
#C24 #C2:24 Lock unit tailgate Ulow /Ubat Ulow /Ubat Open signal
#C25 #C2:25 Reserve - - -
#C26 #C2:26 Brake lamp switch Ulow Ulow /Ubat -
#C27 #C2:27 Start button 1, input/output signal Ubat /Ulow Ubat /Ulow Signal to Keyless vehicle module (KVM)
#C28 #C2:28 Lock motor central lock rear door right, switch Ubat if door open
Ulow in others
Door switch
#C29 #C2:29 Lock motor central lock front door right, switch Ubat if door open
Ulow in others
Door switch
#C30 #C2:30 Lock unit tailgate/Lock motor central lock tailgate, switch Ubat if tailgate open
Ulow in others
Lock unit boot lid: V70
#C31 #C2:31 Reserve - - -
#C32 #C2:32 Reserve - - -
#C33 #C2:33 Fuel level sensor, pump side Ulow U = 0.5-4 V Pulsed signal (PWM), f= 5 Hz (f = 1 Hz for flexifuel vehicles),
#C34 #C2:34 Accelerator pedal position sensor, input signal - U = 0-5 V -
#C35 #C2:35 Rear axle sensor, control signal Ulow /Ulow U = 0-5 V with ignition on Spare on vehicles before model year 2012
#C36 #C2:36 Reserve - - -
#C37 #C2:37 Reserve - - -
#C38 #C2:38 Reserve - - -
#C39 #C2:39 Lock unit tailgate - - Lock signal, only V70
Spare from structure week 2010 46.
#C40 #C2:40 Reserve - - -
#C41 #C2:41 Clutch pedal switch, internal, 75%. Ulow /Ubat Ulow /Ubat Signal to Engine control module (ECM) and Transmission control module (TCM)
#C42 #C2:42 Clutch pedal switch, internal, 75%. Ulow /Ubat Ulow /Ubat -
#C43 #C2:43 LIN-bridge between Keyless vehicle module (KVM) and remote receiver (RKE) During communication the voltage is UV low - Ubat Only vehicles with keyless entry (KVM)
#C44 #C2:44 Rear left turn signal lamp, power supply Ulow Ubat -Ulow /Ulow Flashing hazard lights also work with ignition off.
#C45 #C2:45 Brake light switch, input signal Ubat /Ulow Ubat /Ulow -
#C46 #C2:46 Reserve - - -
#C47 #C2:47 Rear right parking lamp, power supply Ubat /Ulow Ubat /Ulow -
#C48 #C2:48 License plate lighting, power supply Ubat /Ulow Ubat /Ulow -
#C49 #C2:49 Rear left parking lamp, power supply Ubat /Ulow Ubat /Ulow -
#C50 #C2:50 Emergency brake light, power supply Ubat /Ulow Ubat /Ulow Certain markets only
#C51 #C2:51 Fuel level sensor, ground Ulow Ulow -
#C52 #C2:52 Accelerator pedal position sensor, ground Ulow Ulow -
#C53 #C2:53 Rear axle sensor, ground Ulow /Ulow Ulow /Ulow Spare on vehicles before model year 2012
#C54 #C2:54 Rear fog lamp, power supply Ulow Ubat /Ulow -
#C55 #C2:55 Brake light switch, 30-power supply Ubat Ubat -
#C56 #C2:56 Reserve - - -
#C57 #C2:57 Reserve - - -
#C58 #C2:58 Sensor accelerator pedal, 15-voltage feed Ulow Ulow Ubat Via relay 15-feed, electrical distribution box engine compartment
#C59 #C2:59 Left brake light,
Brake light signal for trailer
Ubat /Ulow Ubat /Ulow For V70 both left and right brake light is connected to #C2:59.
#C60 #C2:60 Right brake light Ubat /Ulow Ubat /Ulow Spare on V70.
#D1 #C2:61 Reserve - - -
#D2 #C2:62 Tank hatch, voltage feed for unlocking Ubat /Ulow Ubat /Ulow -
#D3 #C2:63 Lock unit tailgate, unlocking, voltage feed Ubat /Ulow Ubat /Ulow -
#D4 #C2:64 Rear wiper motor, voltage feed Ulow Ubat -
#D5 #C2:65 Power ground Ulow Ulow -
#D6 #C2:66 Heartbeat sensor (HBS) and Mass movement sensor (MMS), 30-power supply Ubat Ubat Mass movement sensor only for XC60 with panorama roof. Heart beat sensor only for vehicles before model year 2011.
#D7 #C2:67 Reserve - - -
#D8 #C2:68 Reserve - - -
#D9 #C2:69 Rear right turn signal lamp, power supply Ulow Ubat -Ulow /Ulow Flashing hazard lights also work with ignition off
#D10 #C2:70 Interior lighting for luggage compartment, switch closing tailgate, lock unit tailgate, control unit electrically operated passenger seat (PSM) and switch power window driver door, voltage feed Ulow Ubat -
#D11 #C2:71 Lock unit tailgate, locking Ubat /Ulow Ubat /Ulow Only V70
Spare from structure week 201046.
#D12 #C2:72 Occupant weight sensor (OWS), power supply Ulow Ubat -
#D13 #C2:73 Back-up light left, power supply Ulow Ubat /Ulow For V70 both left and right back-up light are supplied with voltage from #C2:73.
#D14 #C2:74 Back-up light right, power supply Ulow Ubat /Ulow -
#D15 #C2:75 Reserve - - -
#D16 #C2:76 Fuel pump (FP), power supply Ulow Ubat /Ulow -
Fig 3: Identifying 76-Pin Connector
GLL155449Courtesy of VOLVO CARS CORPORATION
Connector C3 (Blue)
Breakout box terminal  Control module terminal  Signal type  Ignition off 
Active/Not active 
Ignition on 
Active/Not active 
Miscellaneous 
#E1 #C3:1 Solar sensor left/right, dusk sensor and alarm diode, ground Ulow Ulow -
#E2 #C3:2 Sun sensor left Ulow U = 0.25 - 4.75 V -
#E3 #C3:3 Start button, input signal 1 Ubat /Ulow Ubat /Ulow -
#E4 #C3:4 Start button, input signal 2 Ubat /Ulow Ubat /Ulow -
#E5 #C3:5 Forward sensing module (FSM), 15-power supply Ulow Ubat Voltage feed via relay 15-feed, electrical distribution box engine compartment
#E6 #C3:6 Communication CAN_H high speed network During communication the voltage is 2.0 - 3.5 V HS CAN
#E7 #C3:7 Communication CAN_L high speed network During communication the voltage is 1.5 - 2.5 V HS CAN
#E8 #C3:8 Reserve - - -
#E9 #C3:9 Reserve - - -
#E10 #C3:10 Symbol lighting start button, voltage feed Ubat Ulow Only vehicles with ignition antenna unit (IAU)
#E11 #C3:11 Reserve - - -
#E12 #C3:12 Horn, switch Ulow /Ubat Ulow /Ubat -
#E13 #C3:13 Hazard flashers, switch Ulow /Ubat Ulow /Ubat -
#E14 #C3:14 ITO collision signal from Supplemental restraint system module (SRS)
Collision signal to telematic module (PHM/TEM) (Volvo On Call)
Normal, f = 10 Hz, PWM = 50%.
Impact registered, f = 250 Hz, PWM = 50%, for up to 5 seconds.
-
#E15 #C3:15 Reserve - - -
#E16 #C3:16 Reserve - - -
#E17 #C3:17 Reserve - - -
#E18 #C3:18 Reserve - - -
#E19 #C3:19 Twilight sensor Ulow U = 0.25 V - 4.75 V -
#E20 #C3:20 Sun sensor right Ulow U = 0.25 V - 4.75 V -
#E21 #C3:21 Reserve - - -
#E22 #C3:22 Reserve - - -
#E23 #C3:23 Reserve - - -
#E24 #C3:24 Reserve - - -
#E25 #C3:25 Reserve - - -
#E26 #C3:26 Reserve - - -
#E27 #C3:27 Reserve - - -
#E28 #C3:28 Reserve - - -
#E29 #C3:29 Reserve - - -
#E30 #C3:30 Reserve - - -
#E31 #C3:31 Reserve - - -
#E32 #C3:32 Reserve - - -
#E33 #C3:33 Reserve - - -
#E34 #C3:34 Reserve - - -
#E35 #C3:35 Reserve - - -
#E36 #C3:36 Reserve - - -
#E37 #C3:37 Hazard flashers, lighting for switches, voltage feed Ubat -Ulow if activated
Ulow in others
Ubat -Ulow when activated
#E38 #C3:38 Reverse lockout, power supply - - -
#E39 #C3:39 Alarm diode, power supply Alarm activated: approx. 2 V 0.5 Hz 5% duty
Alarm triggered: approx. 2 V 4 Hz 25% duty
-
#E40 #C3:40 Reserve - - -
#E41 #C3:41 Reserve - - -
#E42 #C3:42 Positive temperature coefficient (PTC) heater, control signal Ubat Ubat -Ulow /Ubat -
#E43 #C3:43 Switch, trunk lid/tailgate private locking Ulow Ulow /Ubat -
#E44 #C3:44 Communication LIN, Remote Receiver Module (RRX/RKE) The voltage is 0 V - Ubat during communication Remote receiver (RKE) for vehicles with keyless entry (KVM)
Remote receiver (RRX) for vehicles without keyless entry (KVM)
#E45 #C3:45 Reserve - - -
#E46 #C3:46 Communication LIN bus 3 During communication the voltage is 0 V - Ubat Steering column lock module (SCL)
#E47 #C3:47 Communication LIN bus 3 During communication the voltage is 0 V - Ubat Start control module (SCU)
For V70, Ignition antenna unit (IAU)
#E48 #C3:48 Communication LIN bus 1 During communication the voltage is 0 V - Ubat Steering wheel module (SWM)
#E49 #C3:49 Communication LIN bus 1 During communication the voltage is 0 V - Ubat Light switch module (LSM)
#E50 #C3:50 Reserve - - -
#E51 #C3:51 Reserve - - -
#E52 #C3:52 Reserve - - -
#E53 #C3:53 Reserve - - -
#E54 #C3:54 Reserve - - -
#E55 #C3:55 Lighting instep front right and left, voltage feed Ulow /Ubat Ulow /Ubat For V70 from model year 2012 the LED lighting can also be lit when driving in the dark.
#E56 #C3:56 Lighting glove compartment, Ulow Ubat Voltage feed for alcolock (option)
#E57 #C3:57 Reserve - - -
#E58 #C3:58 Reserve - - -
#E59 #C3:59 Reserve - - -
#E60 #C3:60 Reserve - - -
#F1 #C3:61 Steering wheel module (SWM), power supply Ubat Ubat -
#F2 #C3:62 Driver information module (DIM), power supply Ulow Ubat -
#F3 #C3:63 Forward Sensing Module (FSM) and Forward looking radar (FLR) power supply Ulow Ubat -
#F4 #C3:64 Reserve - - -
#F5 #C3:65 Infotainment control module (ICM) and integrated audio module (IAM), 30-voltage feed Ubat Ubat -
#F6 #C3:66 Supplemental restraint system module (SRS), voltage feed Ulow Ubat -
#F7 #C3:67 PTC-heater and switch electrically heated rear seat, 15-voltage feed Ubat with ignition in position II
Ulow in others
-
#F8 #C3:68 Diagnostics socket (OBDII), voltage feed Ubat Ubat -
#F9 #C3:69 Safety lighting, lighting ashtray, symbol lighting parking brake, voltage feed Ubat -Ulow/ /Ulow Ubat -Ulow V70 also voltage feed for symbol lighting, rear headphone socket.
#F10 #C3:70 Reserve - - -
#F11 #C3:71 Reserve - - -
#F12 #C3:72 Reserve - - -
#F13 #C3:73 Climate control module (CCM), 30-voltage feed Ubat Ubat -
#F14 #C3:74 Ignition (SCU) and electronic immobilizer, voltage feed Ubat Ubat Start control module (SCU)
For V70, Ignition antenna unit (IAU)
#F15 #C3:75 Sun roof module (SRM), voltage feed Ubat Ubat -
#F16 #C3:76 Relay, steering column lock module (SCL), power supply Ubat /Ulow Ubat /Ulow -
Fig 4: Identifying 20-Pin Connector
GLL155454Courtesy of VOLVO CARS CORPORATION
Connector C4 (Black)
Breakout box terminal  Control module terminal  Signal type  Ignition off 
Active/Not active 
Ignition on 
Active/Not active 
Miscellaneous 
#B21 #C4:1 Roof hatch, speed signal Ubat Ubat -Ulow /Ubat -
#B22 #C4:2 High level brake light, power supply Ubat /Ulow Ubat /Ulow Only sedan model
#B23 #C4:3 Seat belt reminder LED, power supply Ulow Ubat /Ulow -
#B24 #C4:4 Tank hatch, global closing, control signal Ubat Ulow /Ubat -
#B25 #C4:5 Reserve - - -
#B26 #C4:6 LIN-bridge between remote receiver (RKE) and Keyless Vehicle Module (KVM) During communication the voltage is UV low - Ubat Only for vehicles with keyless entry (KVM).
#B27 #C4:7 Reserve - - -
#B28 #C4:8 Reserve - -
#B29 #C4:9 Communication LIN bus 2 During communication the voltage is UV low - Ubat Movement sensor (IMS)
#B30 #C4:10 Communication LIN bus 8 During communication the voltage is UV low - Ubat Rain sensor module (RSM)
#B31 #C4:11 Automatic dimming interior rearview mirror and Rain sensor, 15-voltage feed Ulow Ubat -
#B32 #C4:12 Reserve - - -
#B33 #C4:13 Reserve - - -
#B34 #C4:14 Interior lighting roof, voltage feed - Ulow /Ubat -
#B35 #C4:15 Reserve - - -
#B36 #C4:16 Reserve - - -
#B37 #C4:17 Reserve - - -
#B38 #C4:18 Rain sensor (RMS), make-up mirror lighting, rear roof light, front roof light, voltage feed Ulow Ubat -
#B39 #C4:19 Remote receiver (RKE, RRX), voltage feed Ubat Ubat Remote receiver (RKE) for vehicles without keyless entry (KVM).
Remote receiver (RRX) for vehicles with keyless entry (KVM).
#B40 #C4:20 Movement sensor (IMS), 30-power supply Ubat Ubat -