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Home >> Volvo >> 2007 >> S60 Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Headlights >> Headlamp Control Module (HCM) - Specifications, Electrical/Electronic >> Signal Description, Headlamp Control Module (HCM) (2007-2009) >> Signal Specification
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Signal Specification

General 

All the values given below are between the respective terminal in column 1 and terminal #A6 in column 1 (power ground), if this is not the case, it is indicated within brackets.

NOTE: It is important to check ground terminals before taking readings.
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 as a % - -
Fig 1: Identifying Headlamp Control Module
GLL156338Courtesy of VOLVO CARS OF NORTH AMERICA.
Signal table

Control module terminal  Signal type Ignition off Active/Inactive  Ignition on Active/Inactive  Other 
#A1 15-feed U low /Ulow Uhigh /Uhigh -
#A2 - - - -
#A3 Communication CAN_L high speed network During communication the voltage is 1.5-2.5 V -
#A4 Communication CAN_H high speed network During communication the voltage is 2.0-3.5 V -
#A5 Left headlamp control unit (LHCU), LIN communication During communication the voltage is 0 V - Ubat -
#A6 Power ground U low /Ulow U low /Ulow -
#A7 Right headlamp control unit (RHCU), LIN communication During communication the voltage is 0 V - Ubat -
#A8 - - - -
#A9 - - - -
#A10 - - - -
#A11 - - - -
#A12 - - - -
#A13 - - - -
#A14 - - - -
#A15 - - - -
#A16 - - - -