Fog/Driving Lamp: Description and Operation

FRONT FOG LAMPS
With the ignition switch in the ON or START position, the front fog lamps will illuminate when the driver places the front fog lamp switch in the ON position. The front fog lamps will deactivate when the high beam headlamps are turned ON. The underhood fuse block supplies battery positive voltage to the switch circuit of the FOG LP relay. Ignition voltage is available to the FOG LP relay coil. The dash integration module (DIM) controls the FOG LP relay coil. When the front fog lamp switch is ON, the front fog lamp input of the instrument panel integration module (IPM) has ground. In response to this input, the IPM sends a class 2 message to the DIM, which energizes the FOG LP relay. The IPC illuminates the front fog lamp indicator when the IPC receives a class 2 message from the DIM after the front fog lamps have been requested. When the DIM energizes the FOG LP relay, the current flows from the FOG LP relay switch to both front fog lamps. The front fog lamps have ground at G401. The state of the front fog lamps (ON or OFF) will remain the same until the front fog lamp switch is pressed again, even between ignition cycles. When the front fog lamps are on, the park lamps will also be activated.

REAR FOG LAMPS
With the ignition switch in the ON or START position and the headlamps or the front fog lamps are ON, the rear fog lamps will illuminate when the driver places the rear fog lamp switch in the ON position. The rear fog lamps will return to OFF between ignition cycles. If a flash-to-pass function is performed, the rear fog lamps will not turn OFF. The rear compartment relay center supplies battery positive voltage to the switch circuit of the RR FOG LP relay. Ignition voltage is available to the RR FOG LP relay coil. The rear integration module (RIM) controls the RR FOG LP relay coil. When the rear fog lamp switch is placed in the ON position, the rear fog lamp input of the instrument panel integration module (IPM) has ground. In response to this input, the IPM sends a class 2 message to the RIM, which energizes the RR FOG LP relay. The IPC illuminates the rear fog lamp indicator when the IPC receives a class 2 message from the RIM after the rear fog lamps have been requested. When the RIM energizes the RR FOG LP relay, the current flows from the RR FOG LP relay switch to both rear fog lamps. The rear fog lamps have ground at G402.