Fog Lamp Indicator
The fog lamp indicator gives an indication to the vehicle operator whenever the optional fog lamps are illuminated. This indicator is controlled by a transistor on the CCN circuit board based upon programming and electronic messages from the Total Integrated Power Module (TIPM) over the CAN data bus.
The 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 fog lamp indicator for the following reasons:
- Fog Lamp-ON Message - Each time the CCN receives a fog lamp-on message from the TIPM indicating the fog lamp relay is energized, the fog lamp indicator will be illuminated. The indicator remains illuminated until the cluster receives a fog lamp-off message from the TIPM.
The CCN continually monitors a hard wired input from the headlamp switch to determine the selected fog lamp switch status. The CCN then sends the proper fog lamp-on and lamp-off messages to the TIPM over the CAN data bus. The TIPM activates the fog lamp relay then sends the proper fog lamp indicator lamp-on and lamp-off messages to the CCN.