Control module

The main task of the phone module (PHM) is to manage the following functions for voice calls.

The phone module (PHM) is integrated in the keypad, which is beside the audio module (AUM) in the center console. A phone box containing the GSM unit is part of the control module. The phone box is located in the cargo compartment. If the phone module (PHM) is replaced, the keypad must also be replaced.

The phone module (PHM)communicates partly with components which are directly connected and partly with other control modules and components via serial communication.

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.

In the event of communication problems between the phone module (PHM) and the phone box, a text message indicating that the carphone is not working will be displayed in the driver information module (DIM).

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 car.

An easy way to check that the phone module (PHM) is powered and grounded is to switch on the carphone. Press the ON/OFF button and then the YES button to access the carphone menu. The LED in the ON/OFF button should then be on and a text message displayed in the driver information module (DIM).

The phone module (PHM) has an integrated SIM (Subscriber Identity Module) card reader in the phone box. The SIM card reader is designed for the large SIM card which is inserted into the phone box. An adapter/holder must be used if the customer wishes to use the small SIM card from a mobile phone.