Phone Module (PHM) (2008-2009): Design: Handset

Fig 1: Identifying Handset

Courtesy of VOLVO CARS CORPORATION

The handset is directly connected to the phone module (PHM). The handset is located in the center console beneath the cover.

The phone module (PHM) determines if the call is to be connected via handsfree or handset from the click signal of the handset. When the handset is in the holder all calls are connected via handsfree. The handset is activated when it is removed from the holder. Note that voice calls do not go via the handset if it is lifted when an incoming call arrives or when an out going call is started using the ENTER button. The handset must be replaced and then lifted again for conversations via the handset. The reason for this is to avoid missing sound when the handset has been lifted accidentally. The click signal to the phone module (PHM) is controlled by a magnetic switch placed in the handset. The switch is closed by the magnet in the handset. When the handset is in the holder the click signal to the phone module (PHM) is 0 V, when the handset is used the signal is 5 V.

There are diagnostics for the handset.