Rear Fog Lamps

Rear fog lamps are installed on vehicles manufactured for certain export markets where they are required. The rear fog lamp system includes the headlamp switch, the IC and the BCM. The rear fog lamp bulbs have a path to ground at all times through a takeout and eyelet terminal of the body wire harness that is secured to the body sheet metal.

The BCM monitors a hard wired multiplex input from the headlamp switch to determine whether the rear fog lamps are selected. The BCM responds to this input by controlling a battery voltage output to the rear fog lamp bulbs through a high side driver on the rear fog lamp signal control circuit. The BCM also sends the appropriate electronic messages to the IC to control the rear fog lamp indicator.

The BCM will automatically energize and de-energize the front fog lamps in concert with the rear fog lamps. The BCM also provides a battery saver (load shedding) feature for the rear fog lamps, which will turn these lamps OFF if they are left ON for more than about eight minutes with the ignition switch in the LOCK position.