Front Fog Lamp Indicator

The front fog lamp indicator gives an indication to the vehicle operator whenever the front fog lamps are illuminated. This indicator is controlled by a transistor on the IPC circuit board based upon IPC programming and electronic messages received by the IPC from the BCM over the CAN data bus.

The front fog lamp indicator LED is completely controlled by the IPC logic circuit, and that logic will allow this indicator to operate whenever the IPC receives a battery current input on the fused B(+) circuit. Therefore, the LED can be illuminated regardless of the ignition switch position. The LED only illuminates when it is provided a path to ground by the IPC transistor. The IPC will turn ON the front fog lamp indicator for the following reasons:

• Front Fog Indicator Lamp-On Message  - Each time the IPC receives an electronic front fog indicator lamp-ON  message from the BCM indicating the front fog lamps are turned ON, the front fog lamp indicator will be illuminated. The indicator remains illuminated until the IPC receives a lamp-OFF message from the BCM, or until the exterior lamp load shedding (battery saver) timed interval expires, whichever occurs first.

The BCM continually monitors electronic exterior lighting request  messages from the IPC to determine the appropriate outputs to the front fog lamps. The BCM activates or deactivates the front fog lamps then sends the proper lamp-ON or lamp-OFF message back to the IPC.