Circuit Description

The Instrument Panel Integration Module (IPM) receives an input from instrument panel dimmer switch. IPM supplies the ground for the switch through the sensor return line. Instrument panel dimmer switch resistance varies between 0-40,000 ohms as switch is operated. As resistance varies, voltage input to IPM changes. IPM determines level of dimming/illumination.

IPM sends a message via the Class-II serial data line to the Dash Integration Module (DIM), the Driver Door Module (DDM), the Instrument Cluster (IPC), the radio (IRC), and the cellular telephone docking station (PHN) to control level of dimming/illumination. DTC will set anytime IPM detects that the instrument panel dimmer switch input voltage is out of range.