Normal Operation

WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.

The headlamp switch supplies the instrument cluster with the headlamp switch position status. The dimmer switch provides the instrument cluster with the dimmer control status through signal circuit 8-LE10 (WH/BK) and return circuit 9-LE10 (BN/YE). The instrument cluster sends the illumination message to the front electronic module (FEM) over the standard corporate protocol (SCP) communication network, circuits 4-EG8 (GY/VT) and 5-EG8 (BU/WH), based upon the dimmer switch position. The FEM is supplied with illumination voltage through circuit 29S-DK22 (OG/YE) whenever the switched system power (SSP) is energized. When the headlamp switch is in the PARK, HEADLAMP, or AUTOLAMP ON position, the instrument cluster sends the FEM an illumination message and the FEM, in turn, provides a pulse width modulation (PWM) voltage to the interior auxiliary junction box through circuit 64S-LH5 (BU/RD). The interior auxiliary junction box separates the PWM voltage and supplies it to sub-illumination sources through circuits 64S-LH4 (BU/RD), 64S-LH1 (BU/RD), 64S-LK9 (BU/RD), 64S-LH16 (BU/WH), 64S-LK1 (BU/RD), and the central junction box (CJB) through circuit 64S-AD2 (BU/RD). The CJB separates the PWM voltage and also supplies it to the sub-illumination sources through circuits 64S-LH2 (BU/RD) and 64S-LH33 (BU/BK). The sub-illumination sources then provide the PWM voltage to the individual illuminating sources. If the dimmer switch signal and return circuits or the dimmer switch are open, the instrument cluster defaults the FEM to maximum intensity.