Circuit/System Description

2008 Chevrolet Chevy Express G3500, Van Passenger ExtendedSECTION Circuit/System Description
WARNING: This page is about a different car, the 2010 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.

With the headlamp switch in the ON position, the headlamp switch headlamp ON signal circuit is grounded through the turn signal/multifunction switch. In response to this input, the instrument panel module provides ground to either the headlamp low beam relay control circuit or the headlamp high beam relay control circuit. The position of the headlamp dimmer switch determines which relay coil has ground. The instrument panel module supplies ground to the relay coil circuits, if the headlamps are necessary. The underhood fuse block supplies battery positive voltage to both relay switch circuits. When the low beam relay coil is energized, current flows through the LT LOW BEAM and the RT LOW BEAM fuses to the low beam headlamps.

RENDER: 1.0x

NO RELATED

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