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Home >> Volvo >> 2009 >> XC70 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Electrical Modules And Components - Design And Function - 4 Of 5 >> Phone Module (PHM) (2008 - 2009 Early) >> System Overview >> Control Module
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Control Module

Fig 1: Identifying Phone Module (PHM)
GLL152309Courtesy of VOLVO CARS CORPORATION

Two versions of the phone module (PHM) are available, with or without Volvo On Call functionality (market dependent).

The main function of the phone module (PHM) is to manage functions for: 

The control module is located above the glove compartment inside the dashboard.

Phone module (PHM) with Volvo On Call functionality cannot be retro fitted.

The phone module (PHM) communicates partly with directly connected components and partly with other control modules via the CAN and MOST networks. All diagnostic communication between VIDA and the phone module (PHM) occurs via the CAN network.

The phone module (PHM) does not have its own keypad. The menus are instead navigated using the climate control module (CCM) keypad and the infotainment control module (ICM) display.

The control module checks activations and input and output signals via an integrated diagnostic system. A diagnostic trouble code (DTC) is stored if the control module detects an error. In certain cases the control module replaces the faulty signal with a substitute value.

For phone modules (PHM) with Volvo On Call functionality the driver will be alerted by a message in the driver information module (DIM) when a diagnostic trouble code (DTC) is stored.

Any diagnostic trouble codes (DTCs) are stored in the control module memory. This information can be read off using VIDA via the data link connector (DLC) in the vehicle.

If the phone module (PHM) is not supplied with voltage there will be no communication with the MOST network and the system will shut off.

The phone module (PHM) has a SIM card reader for the customer private telephone subscription. For phone modules (PHM) with the Volvo On Call function there is also an internally mounted SIM card. This subscription is only connected to the service center which supplies Volvo On Call services.

The following applies to phones with Volvo On Call 

A started Volvo On Call service will always have higher priority than a call via the customer's private telephone subscription. A normal phone call will either not be possible or will be interrupted while a Volvo On Call service is active.

The phone module (PHM) with Volvo On Call function has an integrated backup battery.

The backup battery ensures that the control module has power when a Volvo On Call service is activated if battery voltage is not available. The remaining backup battery capacity is calculated by the control module. If the battery is replaced, the capacity level must be reset to fully charged. This is done using VIDA (Volvo scan tool). A diagnostic trouble code is generated once calculated capacity reaches 30%. The estimated service life of the backup battery is 4 years.

The phone module (PHM) with Volvo On Call function has a reserve microphone and reserve loudspeaker. The loudspeaker is located internally in the control module and the microphone is located by the switches for Volvo On Call. The reserve microphone and the reserve loudspeaker are only used when a Volvo On Call service is activated and the normal loudspeaker and handsfree microphone are not available.

The phone module (PHM) with the Volvo On Call function has an integrated reserve antenna. This is located internally in the control module. The reserve antenna is only used when a Volvo On Call service is activated and when the normal antenna does not function.