Phone Module (PHM) (2001-2007): Function: Carphone
The phone module (PHM) (16/60) menu can be controlled via the steering wheel buttons (3/131) on the right-hand side of the steering wheel module (SWM) (3/130) or by using the keypad for the phone module (PHM). When controlling the menu via the steering wheel buttons, the YES button is used to access the menu selection and then to select the required menu. The NO button is used to scroll backwards in the menus. The left and right arrows are used to shift between different menus.
The menus are displayed for the user in the text window in the driver information module (5/1). When using the phone handsfree, the +/- buttons are used to lower and raise the volume. The signals between the steering wheel module (SWM), phone module (PHM) and driver information module are transmitted on the CAN network. For safety reasons certain functions cannot be used at speeds above 8 km/h (this safety feature can be disconnected). However any function in use can be completed.
When a call is connected using handsfree, the carphone module (PHM) transmits a request via the CAN network to the audio module (AUM) (16/1) to mute the volume and to pause any CD playback.
The lighting in the keypad is controlled via a rheostat in the light switch module (LSM) (3/111). The phone module (PHM) receives the rheostat signal on the CAN network via the central electronic module (CEM) (4/56).
The carphone system has ASC (Active Sound Control). This means that the handsfree speaker is automatically adjusted to the car speed to compensate for noise. ASC can be disengaged using the menus for the carphone system. The phone module (PHM) receives a signal with speed data from the brake control module (BCM) (4/16).