Rear Fog Lamp Indicator

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

The rear fog lamp indicator LED is completely controlled by the CCN logic circuit, and that logic will allow this indicator to operate whenever the instrument cluster 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 CCN transistor. The CCN will turn ON the rear fog lamp indicator for the following reasons:

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

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