Principles of Operation

WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: The smart junction box (SJB) is also known as the generic electronic module (GEM).

NOTE: When installing a new SJB, it must be configured for this feature, if originally equipped. Refer to MODULE CONFIGURATION .

The SJB controls the daytime running lamps (DRL) by using various inputs to determine whether or not the DRL should be illuminated. These inputs include:

Ignition switch position
Headlamp switch position
Headlamps on or off
Transaxle gear selection

When the DRL is active, the SJB provides a pulse-width modulated (PWM) voltage to the low beam headlamps. This illuminates the headlamps at a reduced intensity.