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Signal Specification

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Fig 1: Ground Terminals
GLL104191Courtesy of VOLVO CARS CORPORATION
NOTE: It is important to connect the breakout box and check the ground terminals before taking readings.

Other information 

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) - -
Connector A, terminals #A1-#A20
The following values are measured between the relevant terminal in column 1 and terminal #E1 (power ground) unless otherwise stated.
NOTE: Check the ground terminals before starting to take readings with the breakout box.

U = DC in volts (V)
Ubat = battery voltage in volts (V)
Ulow = Voltage close to 0 V
Breakout box terminal  Terminal in connector  Signal type  Ignition off  Ignition on  Other 
- - - Activated  Not activated  Activated  Not activated  -
#A1 #A1 Signal (-) back-up (reversing) lamp Ulow Ubat Ulow Ubat -
#A2 #A2 Signal, for fault-tracing the actuator motor for the left-hand xenon lamp Ulow Ulow Ulow-Ubat if active,
Ulow otherwise in pulse ratio (%duty) = 0-100%
A fault is detected at 65% > pulse ratio (%duty) > 90%
#A3 #A3 Control signal, starter motor relay - 0 V 0 V Activated with key in position III
#A4 #A4 Signal, Hood switch Ulow with the hood closed
Ulow-Ubat with the hood open
Pulsed signal, f=100 Hz
#A5 #A5 Signal (-) L-signal Ulow Ulow Ubat U~0.3-0.7*Ubat -
#A6 #A6 Stepper motor speed related power steering (channel B) Ulow Ulow-Ubat Ulow signal for 12 ms
#A7 #A7 Stepper motor speed related power steering (channel A) Ulow Ulow-Ubat Ulow signal for 12 ms
#A8 #A8 Control signal relay for headlamp washing Ulow Ubat Ulow Ubat -
#A9 #A9 Pulse width modulated signal (+) to beam adjustment unit Ulow Ulow-Ubat if active, Ulow otherwise
Pulse ratio (% duty) > 0%
Pulse ratio increases with increased beam width
#A10 #A10 - - - -
#A11 #A11 Stepper motor speed related power steering (channel B) Ulow Ulow-Ubat Ulow signal for 12 ms
#A12 #A12 Stepper motor speed related power steering (channel A) Ulow Ulow-Ubat Ulow signal for 12 ms
#A13 #A13 Control signal, windshield wiper relay off/on Ubat Ulow Ubat -
#A14 #A14 Control signal, windshield wiper high speed relay Ubat Ulow Ubat -
#A15 #A15 Glass breakage loop, pulsed signal 0-12 V Ulow Ulow 0-12 V periodically when the car is alarmed
#A16 #A16 Control signal, front washer motor relay Ubat Ulow Ubat -
#A17 #A17 Control signal, rear washer motor relay Ubat Ulow Ubat (5 DRS)
#A18 #A18 Volcano Lite The voltage is 0 V - Ubat during communication Serial communication
#A19 #A19 Control signal, horn relay Ulow Ubat Ulow Ubat -
#A20 #A20 Signal (-), starter motor relay Ulow Ubat Ulow -
Connector B, terminals #B1 - #B20
The following values are measured between the relevant terminal in column 1 and terminal #E1 (power ground) unless otherwise stated.
NOTE: Check the ground terminals before starting to take readings with the breakout box.

U = DC in volts (V)
Ubat = battery voltage in volts (V)
Ulow = Voltage close to 0 V
Breakout box terminal  Terminal in connector  Signal type  Ignition off  Ignition on  Other 
- - - Activated  Not activated  Activated  Not activated  -
#A21 #B1 S-supply (Power supply from ignition switch) Ulow (Key out), Ubat (key in) -
#A22 #B2 X-supply (Power supply from the ignition switch) Ubat (Key in positions I and II); Ulow otherwise -
#A23 #B3 15-supply (Power supply from ignition switch) Ubat (Key in positions II and III); Ulow otherwise -
#A24 #B4 Stop lamp switch signal Ubat Ulow Ubat Ulow -
#A25 #B5 Supply upper stop lamp (4 door) Ubat 6 V Ubat 6 V -
#A26 #B6 Supply to stop lamp relay in the rear electronic module Ulow Ubat Ulow Ubat -
#A27 #B7 Diagnostic communication (CAN H) for the high speed network The voltage is 2.0-3.5 V during communication -
#A28 #B8 Diagnostic communication (CAN_L) for the high speed network The voltage is 1.5-2.5 V during communication -
#A29 #B9 Signal (-) sensor for the front left seat belt buckle Ulow 0-5 V 0-5 V -
#A30 #B10 Reference voltage (+) for X-supply to the left seat belt buckle Ulow Ubat -
#A31 #B11 Serial communication the left heated seat Ulow During communication voltage is ~Ubat -
#A32 #B12 Signal (-) contact breaker (left rear door open) Ulow-Ubat if the door is open, Ulow otherwise Pulsed signal, f=100 Hz.
#A33 #B13 Signal (-) contact breaker (left rear door locked) Ulow if the door is locked, Ubat otherwise -
#A34 #B14 Frequency signal (-) from the Engine Control Module (ECM) for the fuel pump (FP) relay Ulow Frequency signal U=Ulow-Ubat f=50 HZ
#A35 #B15 Signal (-) from the windshield washer reservoir level sensor Ubat if the tank is not empty, Ulow if under 1 liter. -
#A36 #B16 Signal (-) from the windshield wiper motor Ulow Ubat Ulow Ubat Ulow if the engine is running
#A37 #B17 Communication CAN_H high speed network The voltage is 2.0-3.5 V during communication -
#A38 #B18 Communication CAN_L high speed network The voltage is 1.5-2.5 V during communication -
#A39 #B19 Diagnostic communication (CAN_H) for the low speed network The voltage is 2.0-3.5 V during communication -
#A40 #B20 Diagnostic communication (CAN_L) for the low speed network The voltage is 1.5-2.5 V during communication -
Connector C, terminals #C1-#C20
The following values are measured between the relevant terminal in column 1 and terminal #E1 (power ground) unless otherwise stated.
NOTE: Check the ground terminals before starting to take readings with the breakout box.

U = DC in volts (V)
Ubat = battery voltage in volts (V)
Ulow = Voltage close to 0 V
Breakout box terminal  Terminal in connector  Signal type  Ignition off  Ignition on  Other 
- - - Activated  Not activated  Activated  Not activated  -
#A41 #C1 Reference voltage (+) for X-supply to the right seat belt buckle Ulow Ubat -
#A42 #C2 Signal (-) sensor for the front right seat belt buckle Ulow 0-5 V 0-5 V ---
#A43 #C3 Signal (-) contact breaker (right rear door locked) Ulow if the door is locked, Ubat otherwise - -
#A44 #C4 Serial communication right heated seat Ulow During communication voltage is ~Ubat - -
#A45 #C5 Signal (-) Lock unit trunk lid Ulow-Ubat if the tailgate is open, Ulow otherwise - Pulsed signal, f=100 Hz.
#A46 #C6 Control signal, auxiliary lamp relay - Ubat Ulow Ubat -
#A47 #C7 - - - - - -
#A48 #C8 - - - - - -
#A49 #C9 - - - - - -
#A50 #C10 - - - - - -
#A51 #C11 - - - - - -
#A52 #C12 - - - - - -
#A53 #C13 - - - - - -
#A54 #C14 Signal (-) fuel pump (FP) relay switch - Ulow Ubat Ulow -
#A55 #C15 - - - - - -
#A56 #C16 - - - - - -
#A57 #C17 - - - - - -
#A58 #C18 Signal (-) contact breaker (right rear door open) Ulow-Ubat if the door is open, Ulow otherwise Pulsed signal, f= 100 Hz.
#A59 #C19 - - - - - -
#A60 #C20 Reserve (-) - - - - -
Connector D, terminals #D1-#D20
The following values are measured between the relevant terminal in column 1 and terminal #E1 (power ground) unless otherwise stated.
NOTE: Check the ground terminals before starting to take readings with the breakout box.

U = DC in volts (V)
Ubat = battery voltage in volts (V)
Ulow = Voltage close to 0 V
Breakout box terminal  Terminal in connector  Signal type  Ignition off  Ignition on  Other 
- - - Activated  Not activated  Activated  Not activated  -
#B1 #D1 Control signal automatic gear selector module, switch to ground - Ubat Ulow -
#B2 #D2 Communication CAN L low speed network The voltage is 1.5-2.5 V during communication -
#B3 #D3 Communication CAN_H low speed network The voltage is 2-3.5 V during communication -
#B4 #D4 Signal (-) from control stalks (Limp Home) Ubat Ulow Ubat Ulow -
#B5 #D5 Signal (-) from the SRS-control module (airbag OK) Ubat for 200 ms if the airbag is triggered, Ulow if the airbag is not triggered. -
#B6 #D6 Serial communication (K-line), diagnostic The voltage is 0 V - Ubat during communication -
#B7 #D7 Signal (-) contact breaker (left front door open) Ulow-Ubat if the door is open, Ulow otherwise. Pulsed signal, f= 100 Hz.
#B8 #D8 Signal (-) contact breaker (right front door open) Ulow-Ubat if the door is open, Ulow otherwise. Pulsed signal, f= 100 Hz.
#B9 #D9 Signal (-) from the gear-shift position sensor (locked in P/N) Ulow Ulow Ulow Ubat Ulow in P and N position
#B10 #D10 Signal (+), speed (frequency signal) Ulow Ulow-Ubat Frequency signal increases with speed
#B11 #D11 Signal, for fault-tracing the actuator motor for the right-hand xenon lamp Ulow Ulow Ulow-Ubat if active,
Ulow otherwise in pulse ratio (% duty) = 0-100%
A fault is detected at 65%>pulse ratio (%duty)>90%
#B12 #D12 Signal (-) from horn switch Ulow Ubat Ulow Ubat -
#B13 #D13 Signal (+) data Immobilizer Ulow Ubat -
#B14 #D14 Signal (+) Immobilizer Ulow Ubat -
#B15 #D15 - - - - - -
#B16 #D16 Signal (-) switch for the hazard warning signal flasher Ulow if the button is held in, Ubat otherwise -
#B17 #D17 Pulse width modulated signal (+) lamp in button for hazard warning signal flasher Ulow-Ubat if active, Ulow otherwise
Pulse ratio (% duty) > 0%
-
#B18 #D18 Signal (+) glove compartment lighting Ubat 30 minutes after ignition off, Ulow
#B19 #D19 Signal (+) ignition switch illumination Ubat Ulow Ubat Ulow -
#B20 #D20 Signal (+) Alarm indicator LED Ulow or 0.7 V Ulow 0.7 V if the LED is active
Connector E, terminals #E1-#E8
The following values are measured between the relevant terminal in column 1 and terminal #E1 (power ground) unless otherwise stated.
NOTE: Check the ground terminals before starting to take readings with the breakout box.

U = DC in volts (V)
Ubat = battery voltage in volts (V)
Ulow = Voltage close to 0 V
Breakout box terminal  Terminal in connector  Signal type  Ignition off  Ignition on  Other 
- - - Activated  Not activated  Activated  Not activated  -
#B21 #E1 Power ground Ulow -
#B22 #E2 Pulse width modulated signal (+) courtesy lighting Ulow-Ubat if active, Ulow otherwise - -
#B23 #E3 30-supply to turn signal lamps and hazard warning signal flasher Ubat - -
#B24 #E4 - - - - - -
#B25 #E5 - - - - - -
#B26 #E6 30-supply to the central electronic module (CEM) Ubat -
#B27 #E7 - - - - - -
#B28 #E8 Pulse width modulated signal (+) to rheostat Ulow-Ubat if active, Ulow otherwise - -