Input Signals PHM

Audio signals from the handsfree microphone (via telephone box).

GSM communication from the telephone antenna (via telephone box).

Audio signal from the handset.

The central electrical module (CEM) sends the following signals to the phone module (PHM):

• The signal controlling the keypad lighting.
• The vehicle speed, taken from ABS, controls the telephone system sound level (ASC - Automatic Sound Control).
• Identification of the ignition key transponder for access to PIN.
• Control signals from the keypad in the steering wheel hub.
• Global parameters.
• Signals from VIDA via data link connector (DLC).

The signal controlling the keypad lighting is a combination of the signal from the sun sensor which is connected to the CCM and the rheostat connected to the light switch module.

The keypad in the Steering wheel hub are connected to the steering wheel module which sends to the phone module (PHM) keypad. When the phone module is activated the telephone system has precedence and the steering wheel audio keypad is put out of function. If the phone module receives a signal indicating that the steering wheel module does not function all signals from the steering wheel module will be ignored.

Global parameters can be, for example, language selection.