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Home >> Volvo >> 2007 >> C70 Automatic >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Headlights >> Gas Discharge Lamp Module (GDL) And Headlamp Control Module (HCM) - Signal Specifications >> Signal Description, Headlamp Control Module (HCM) >> Signal Specification
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Signal Specification

General 

All values below are measured between the relevant terminal in column 1 and terminal #2F in column 2 (power ground). Unless otherwise stated in parenthesis after the table entry.

NOTE:

It is important to connect the breakout box and check the ground terminals before taking readings.

       
U= DC voltage in volts (V) Ulow = Voltage approximately 0 V
Ubat = Battery voltage (V)    

Connector, headlamp control module (HCM) 

Fig 1: Identifying Headlamp Control Module (HCM) Connector Terminals
GLL161103Courtesy of VOLVO CARS CORPORATION
Control module terminal Signal type Ignition on Other
1A - H1 - - -
2A Communication CAN_L high speed network The voltage is 1.5-2.5 V during communication  
2B - - -
2C Left headlamp control unit (LHCU), LIN communication During communication the voltage is 0V - U bat  
2D Position sensor, ground Ulow  
2E Front position sensor, signal 0.5-4.5V  
2F Power ground Ulow  
2G - - -
2H - - -
3A Communication CAN_H high speed network The voltage is 2.0-3.5 V during communication  
3B Internal signal    
3C Right headlamp control unit (RHCU), LIN communication During communication the voltage is 0V - U bat  
3D Position sensor, voltage supply 5V  
3E Rear position sensor, signal 0.5-4.5V  
3F 15-feed Ubat  
3G - - -
3H - - -
4A - 4H - -

Connector, front and rear position sensors 

Fig 2: Identifying Front And Rear Position Sensor Connector Terminals
GLL153795Courtesy of VOLVO CARS CORPORATION
FRONT POSITION SENSOR

Position sensor connection Control module terminal Signal type Other
1 2D Ground  
2 - -  
3 - -  
4 2E Signal, position sensor  
5 3D Power supply, +5V  
6 - -  
REAR POSITION SENSOR

Position sensor connection Control module terminal Signal type Other
1 2D Ground  
2 - -  
3 - -  
4 3E Signal, position sensor  
5 3D Power supply, +5V  
6 - -