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Signal Specification

WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 2014 Volvo XC90, 2013 Volvo XC90, 2012 Volvo XC90, 2011 Volvo XC90, and 2010 Volvo XC90. However, it is still accessible from the selected car via links, so may be relevant.

All the values given below are between the terminals stated in column 1 and terminal #D6 in column 2 (power ground). This applies unless otherwise indicated in the last column.

NOTE: It is important that the breakout box is connected and that the ground connections have been checked before starting to measure.
Fig 1: Identifying Breakout Box
GLL150240Courtesy of VOLVO CARS CORPORATION
Fig 2: Identifying Connector A
GLL146490Courtesy of VOLVO CARS CORPORATION
U= DC voltage in volts (V) t = Time in milliseconds (ms)
Ubat = Battery voltage (V) f = Frequency in Hertz (Hz)
Ulow = Voltage approximately 0 V % duty Duty cycle (pulse ratio) as a percentage (%)
Connector A
Breakout box terminal  Control module terminal  Signal type  Ignition off 
Active/Not active
Ignition on 
Active/Not active
Miscellaneous 
#1 #A1 Reserve - - -
#2 #A2 Reserve - - -
#3 #A3 Extended X-supply (3) Ulow Ubat (Ignition switch position I & II) XC90, Infotainment.
#4 #A4 Bifuel, power supply to the rear electronic module (REM) Ulow Ubat (Ignition switch position II & III) -
#5 #A5 Reserve - - -
#6 #A6 X supply (Voltage supply from ignition switch) Ulow Ubat (Ignition switch position I & II) RTI/Radio
#7 #A7 Reserve - - -
#8 #A8 15-supply (Power supply from ignition switch) Ulow Ubat (Ignition switch position II & III) -
#9 #A9 Reserve - - -
#10 #A10 Extended X-supply (1) Ubat Ubat Certain climate functions
#11 #A11 Reserve - - -
#12 #A12 Left turn signal lamp Ulow Ulow -Ubat (Ignition position II) / Ulow Pulsed signal, f = approximately 1.5 Hz
#13 #A13 Reserve - - -
#14 #A14 Reserve - - -
#15 #A15 Stop lamps, power supply Ubat /Ulow Ubat /Ulow Does not go to the centrally located brake light (CAN-signal)
#16 #A16 Fuel pump (FP), power supply Ulow Ubat /Ulow -
#17 #A17 Cigarette lighter, power supply Ulow Ubat -
#18 #A18 Passenger seat heater, power supply Ubat Ubat -
#19 #A19 Driver seat heater, power supply Ubat Ubat -
#20 #A20 Collision signal Ulow Ubat /Ubat Active in the event of a collision
#21 #A21 Reserve - - -
#22 #A22 Power passenger seat, power supply Ulow Ubat -
#23 #A23 Circulation pump saddle tank, voltage feed Ulow Ubat /Ulow Only applies to vehicles from model year 2007
#24 #A24 Reserve - - -
#25 #A25 Extended X-supply (2) Ubat Ubat Ubat for 10 seconds after the key is removed, then Ulow
Gear selector module (GSM).
#26 #A26 Reserve - - -
#27 #A27 Steering wheel angle sensor module (SAS), power supply Ulow Ubat (Ignition switch position II & III) -
#28 #A28 Reserve - - -
#29 #A29 Rear right-hand turn signal lamp, power supply Ulow Ulow -Ubat (Ignition position II) / Ulow Pulsed signal, f = approximately 1.5 Hz
#30 #A30 Reserve - - -
#31 #A31 Reserve - - -
#32 #A32 Reserve - - -
Fig 3: Identifying Connector B
GLL146491Courtesy of VOLVO CARS CORPORATION
Connector B
Breakout box terminal  Control module terminal  Signal type  Ignition off 
Active/Not active
Ignition on 
Active/Not active
Miscellaneous 
#1 #B1 Contact breaker, vacuum pump Ulow Ubat (Ignition switch position II & III) -
#2 #B2 30-supply to the central electronic module (CEM) Ubat Ubat Right low beam
#3 #B3 30-supply to the central electronic module (CEM) Ubat Ubat Left low beam
#4 #B4 Right low beam Ulow Ubat /Ulow Ulow when turning the engine
#5 #B5 Reserve - - -
#6 #B6 Reserve - - -
#7 #B7 Left low beam Ulow Ubat /Ulow Ulow when turning the engine
#8 #B8 Daytime running lamps left Ubat /Ulow Ubat /Ulow -
#9 #B9 Daytime running lamps right Ubat /Ulow Ubat /Ulow -
#10 #B10 Extended X-supply (1) Ubat Ubat Parking heater. Certain climate control functions.
#11 #B11 30-supply to the stop lamp switch Ubat Ubat -
#12 #B12 Reserve - - -
#13 #B13 Reserve - - -
#14 #B14 Reserve - - -
#15 #B15 Power supply to the horn Ubat /Ulow Ubat /Ulow -
#16 #B16 30-supply, fuel pump (FP) Ubat Ubat -
#17 #B17 Front fog lamp, left Ulow Ubat /Ulow -
#18 #B18 Front fog lamp, right Ulow Ubat /Ulow -
#19 #B19 Headlamp washer Ulow Ubat (Ignition switch position I & II) -
#20 #B20 Extended X-supply (2) Ubat Ubat Ubat for 10 seconds after the key is removed, then Ulow
Transmission control module (TCM)
#21 #B21 Front washer motor Ulow Ubat /Ulow -
#22 #B22 Power supply ABS/DSTC Ulow Ubat (Ignition switch position II & III) -
#23 #B23 Voltage supply headlamp alignment Ulow Ubat at ignition switch positions II and III/U low -
#24 #B24 Power supply to the parking lamps Ubat Ubat -
#25 #B25 Siren control module (SCM) Ubat /Ulow Ubat /Ulow -
#26 #B26 30-supply to the engine control module (ECM) Ubat Ubat -
#27 #B27 Full beam, left Ubat /Ulow Ubat /Ulow -
#28 #B28 High beam, right Ubat /Ulow Ubat /Ulow -
#29 #B29 Rear washer motor Ulow Ubat /Ulow -
#30 #B30 Headlamp washer Ulow Ubat /Ulow -
#31 #B31 Left turn signal lamp Ulow Ulow -Ubat / U low -
#32 #B32 Right turn signal lamp Ulow Ulow -Ubat / U low -
Fig 4: Identifying Connector C
GLL146493Courtesy of VOLVO CARS CORPORATION
Connector C
Breakout box terminal  Control module terminal  Signal type  Ignition off 
Active/Not active
Ignition on 
Active/Not active
Miscellaneous 
#1 #C1 Status signal from the left-hand gas discharge lamp module (GDL) Ulow Ubat minus approx. 1.5 V in ignition position II, Ubat in ignition position I; regardless of being active/not active -
#2 #C2 Status signal from the right-hand gas discharge lamp module (GDL) Ulow Ubat minus approx. 1.5 V in ignition position II, Ubat in ignition position I; regardless of being active/not active -
#3 #C3 Windshield wiper, high speed Ulow Ulow if wipers not on; Ubat only when wipers move intermittently; Ubat when wipers move continuously at low speed; Ulow when the wipers move at high speed -
#4 #C4 Windshield wipers Off/On Ubat Ubat if the wipers are not on; U low only during intermittent wiping; U low when low speed wiping; Ulow during high speed wiping -
#5 #C5 50-supply to the engine control module (ECM) Ulow Ubat only in ignition switch position III -
#6 #C6 Starter motor relay Ulow U= 2.7 V -
#7 #C7 Control signal, starter motor relay Ulow Ubat /Ulow Ubat in ignition switch position 3, otherwise U low
#8 #C8 Reserve - - -
#9 #C9 Auxiliary lamps Ulow Ubat /Ulow -
#10 #C10 Washer fluid level sensor Ubat if the tank is not empty; Ulow if less than 1 litre. -
#11 #C11 Control signal for the right-hand headlamp alignment motor Ulow Ubat /Ulow -
#12 #C12 Control signal for the left-hand headlamp alignment motor Ulow Ubat /Ulow -
#13 #C13 Reserve - - -
#14 #C14 15-supply to the engine control module (ECM) Ulow Ubat (Ignition switch position II & III) / U low otherwise -
#15 #C15 Wake up signal to ECM U = 0V/Ubat . Ignition position I: U = 0V/Ubat. Ignition position II & III: U = Ubat Ubat a time after ignition position 0 or I has been selected. Then 0 V.
#16 #C16 LIN bus communication During communication the voltage is 0V - Ubat -
#17 #C17 Speed signal Ulow Ulow -Ubat Frequency signal, increases with speed
#18 #C18 Reserve - - -
#19 #C19 Parking lamps, left-hand front Ubat /Ulow Ubat /Ulow -
#20 #C20 Parking lamps, right front Ubat /Ulow Ubat /Ulow -
#21 #C21 Communication CAN_H high speed network The voltage is 2.0-3.5 V during communication -
#22 #C22 Communication CAN_L high speed network The voltage is 1.5-2.5 V during communication -
#23 #C23 Communication CAN_H high speed network The voltage is 2.0-3.5 V during communication Brake control module
#24 #C24 Communication CAN_L high speed network The voltage is 1.5-2.5 V during communication Brake control module
#25 #C25 High-pressure cleaning pump Ubat Ulow / Ubat -
#26 #C26 Reserve - - -
#27 #C27 Reserve - - -
#28 #C28 Control signal, gear selector module (GSM) P/N position - Ubat /Ulow -
#29 #C29 Reserve - - -
#30 #C30 Reserve - - -
#31 #C31 Input signal, windshield wipers U= 10.9 V Ulow as long as the wiper arm is not in the start position. When the wiper arm is in the start position, the voltage increases to U = 10.9 V/Not active: U= 10.9 V -
#32 #C32 Volcano Lite CAN H The voltage is 8.5-9.5 V during communication -
#33 #C33 Reserve - - -
#34 #C34 Stop lamp switch signal Ubat /Ulow Ubat /Ulow -
#35 #C35 Stop lamp switch signal Ubat /Ulow Ubat /Ulow -
#36 #C36 Reserve - - -
Fig 5: Identifying Connector D
GLL146492Courtesy of VOLVO CARS CORPORATION
Connector D
Breakout box terminal  Control module terminal  Signal type  Ignition off 
Active/Not active
Ignition on 
Active/Not active
Miscellaneous 
#1 #D1 Courtesy lighting left front Ulow -Ubat / U low Ulow -Ubat / U low Pulsed signal, f = approximately 100 Hz.
#2 #D2 Courtesy lighting right front Ulow -Ubat / U low Ulow -Ubat / U low Pulsed signal, f = approximately 100 Hz.
#3 #D3 Courtesy lighting, left rear Ulow -Ubat / U low Ulow -Ubat / U low Pulsed signal, f = approximately 100 Hz.
#4 #D4 Courtesy lighting, right rear Ulow -Ubat / U low Ulow -Ubat / U low Pulsed signal, f = approximately 100 Hz.
#5 #D5 Reserve - - -
#6 #D6 Power ground U low /Ulow -
#7 #D7 Windshield wipers (Limp Home) Ubat /Ulow Ubat /Ulow -
#8 #D8 X supply (Voltage supply from ignition switch) U bat (Ignition switch positions I and II); Ulow otherwise -
#9 #D9 Signal (+) glove compartment lighting Ubat Ubat 30 minutes after the ignition is switched off, Ulow
#10 #D10 Seat position sensor, driver Ubat / Ubat / -
#11 #D11 Rain sensor Ulow / Ubat Ulow / Ubat -
#12 #D12 Pulse width modulated signal (+) to rheostat Ulow -Ubat if active, Ulow otherwise -
#13 #D13 Signal (+) ignition switch illumination Ubat /Ulow Ubat /Ulow -
#14 #D14 Lamp, switch, hazard warning signal flashers, power supply. Ubat -U low if activated; Ulow otherwise -
#15 #D15 S-supply (Power supply from ignition switch) U bat (Ignition switch positions 0, I, II and III); Ulow otherwise Ulow with key removed.
#16 #D16 15-supply (Power supply from ignition switch) U bat (Key in positions II and III); Ulow otherwise -
#17 #D17 Signal (-) from horn switch Ulow /Ubat Ulow /Ubat -
#18 #D18 Seat position sensor, passenger Ulow Ubat Reference.
#19 #D19 Collision output signal to the phone (from the Supplemental Restraint System Module (SRS)) - - -
#20 #D20 Signal (-) from the SRS-control module (airbag OK) Ubat below 200 ms if the airbag is triggered, U low if the airbag has not deployed. -
#21 #D21 Reserve - - -
#22 #D22 Signal (-) switch for the hazard warning signal flasher. Ulow if button is held in, Ubat otherwise -
#23 #D23 Gear-shift position sensor Ulow Ulow / Ubat Ulow in positions P and N
#24 #D24 LIN bus communication During communication the voltage is 0V - Ubat -
#25 #D25 Seat position sensor, driver - - (Only XC90 USA/CDN)
#26 #D26 Seat position sensor, passenger - - (Only XC90 USA/CDN)
#27 #D27 Sensor, set belt reminder (+) Ulow / Ubat Ubat /Ubat -
#28 #D28 Sensor, seat belt reminder (-) U low /Ulow U low /Ulow -
#29 #D29 Twilight sensor U low /Ulow U=0.25-4.75V -
#30 #D30 Sun sensor U low /Ulow U=0.25-4.75V -
#31 #D31 Communication CAN_H high speed network The voltage is 2.0-3.5 V during communication -
#32 #D32 Communication CAN_H high speed network The voltage is 2.0-3.5 V during communication -
#33 #D33 Communication CAN_H high speed network The voltage is 2.0-3.5 V during communication OBD out
#34 #D34 Communication CAN_H low speed network The voltage is 2.0-3.5 V during communication -
#35 #D35 Communication CAN_H low speed network The voltage is 2.0-3.5 V during communication -
#36 #D36 Communication CAN_H low speed network The voltage is 2.0-3.5 V during communication -
#37 #D37 Communication CAN_H low speed network The voltage is 2.0-3.5 V during communication Via SRS
#38 #D38 Communication CAN_H low speed network The voltage is 2.0-3.5 V during communication Via UEM
#39 #D39 Communication CAN_H low speed network The voltage is 2.0-3.5 V during communication Via DDM
#40 #D40 Communication CAN_H low speed network The voltage is 2.0-3.5 V during communication OBD out
#41 #D41 Volcano Lite CAN H The voltage is 8.5-9.5 V during communication -
#42 #D42 The sun sensor, twilight sensor and alarm LED share a common ground U low /Ulow U low /Ulow -
#43 #D43 Fuel level sensor, left-hand side (+). Switched signal, 5/35 ms. U~Ulow U=0.54-3.96 V Full: 0.54 V Empty: 3.96 V
#44 #D44 Fuel level sensor, right-hand side (+). Switched signal, 5/35 ms. U~Ulow U=0.54-3.96 V Full: 0.54 V Empty: 3.96 V
#45 #D45 Fuel level sensor common ground U low /Ulow U low /Ulow -
#46 #D46 Communication CAN_L high speed network The voltage is 1.5-2.5 V during communication -
#47 #D47 Communication CAN_L high speed network The voltage is 1.5-2.5 V during communication -
#48 #D48 Communication CAN_L high speed network The voltage is 1.5-2.5 V during communication OBD
#49 #D49 Communication CAN L low speed network The voltage is 1.5-2.5 V during communication -
#50 #D50 Communication CAN L low speed network The voltage is 1.5-2.5 V during communication -
#51 #D51 Communication CAN L low speed network The voltage is 1.5-2.5 V during communication -
#52 #D52 Communication CAN L low speed network The voltage is 1.5-2.5 V during communication Via SRS
#53 #D53 Communication CAN L low speed network The voltage is 1.5-2.5 V during communication Via UEM
#54 #D54 Communication CAN L low speed network The voltage is 1.5-2.5 V during communication Via DDM
#55 #D55 Communication CAN L low speed network The voltage is 1.5-2.5 V during communication OBD out
#56 #D56 IMMO Data U low /Ulow The voltage is 0.5-2.5 V during communication Antenna ring/lighting ignition switch
#57 #D57 IMMO Clock U low /Ulow The voltage is 0.5-2.5 V during communication Antenna ring/lighting ignition switch
#58 #D58 LIN bus 2 During communication the voltage is 0 V - U bat SWM/SAS
#59 #D59 Speed signal Ulow Ulow -Ubat Output signal
Frequency signal, increases with speed
#60 #D60 50-supply (Power supply from ignition switch) U bat (Key in position III); Ulow otherwise -