Dodge Repair: Magnum RT fog lights stopped working just like that.

Question
QUESTION: Hello,
fog lights on my 2006 dodge magnum are not working anymore,I did not touch anything.
The power circuit is OK and tested,when we jump the relay they light up.
The command circuit is in fault,I don't know where to go exactly on that command side so I took a chance and changed my switch but wrong pick,it is not the switch either,it's still doesn't working.
I need to know what coming out of that switch,it goes to the cluster and take the can bus to control the ground side of the relay via the pin 26 from the PCM.
I haven't control the wires yet but where is that cluster that we see on Mitchell diagram ?
I have access to OTC genesis scanner and mitchell diagrams.
I need help because I'm lost there.
Thierry

ANSWER: Hi Thierry,
I too have difficulty with this fog lamp circuit. Which is the switch that you use to activate them?
What other items are controlled by that switch? Pin 26 that controls the fog relay is not from the PCM but rather at the front control module of the integrated power module. But it is not clear to me how the fcm gets a signal from the fog lamp switch. So if you can tell me which switch it is that would help.
Roland

---------- FOLLOW-UP ----------

QUESTION: Hello Roland,
The switch used first was the original one then I chose to go with the new one that you just push on that knob to get your fog lights on.
Testing that part of the circuit is not easy I guess,we might need an oscilo but not available right now for me.
We can see on mitchell's diagram that the switch is sending a signal to what they call the "cluster",is it an integrated part of the FCM ?
I'm pretty sure that my first switch is still in good working condition.
Thanks
Thierry

Answer
Hi Thierry,
I found the wiring for the overall headlamp switch. It shows that the fog lamp switch is part of the headlamp switch. The positions of both the head lamp choices and the fog lamp choice is based upon the overall resistance observed at the cluster of the combined settings of the two switches. The resistance is the result of the combined resistance of the headlamp and the fog lamp switches which are wired in parallel, inside the overall switch. It may well be that the internal wire connection for the fog switch is disconnected from the wiring that goes through the headlamp switch so that whether it is on or off is not being 'seen' by the cluster. I would unplug the headlamp switch and measure the resistance between pins one and three to note whether the resistance value changes when you have the fog "on" vs "off". If not, then given that you installed a new fog switch that means there is a problem with the internal wiring of the headlamp switch as regards the parallel track between pins one and three that goes to the fog lamp switch.
Roland
PS Thanks for the rating and nomination. You are welcome to do that again.