So I've been trying to locate what fuse is connected to the fog light on my Cascadia 2009 truck. The fog lights won't turn on and I belive that it is becuase the fuse or relay broke or blew. I checked the manual and the diagram but it won't give me a specific pieace. Does anyone know what the name for the fuse or relay is called?
There isn’t one. It’s powered directly from the SAM Chassis module. If you had access to Detroit Diagnostic Link it may show a code there for open circuit or short to ground. It could also be the switch.
Thank you for responding, can you please elaborate on how I would fix it? I've been trucking for 20 years and this is the first time I went online for a problem, so I don't really know what a Detroit Diagnostic Link is or any codeing aspect. And I have thought about the switch and it was going to be the first thing I would try.
I also forgot to mention that one side of the fog lights stoped working and 2 or 3 weeks lator the other one stoped working. Do you think that it is still a possibility that it was the switch?
Sounds like a bad ground common to all the front lights. Detroit Diesel Diagnostic Link is the software program used to set parameters and do fault diagnosis for n Detroit engines and transmissions, plus Freightliner and WesternStar trucks. Cost $500 per year subscription plus under $1,000 for the adapter to hook to a laptop.
Just looked at the wiring diagrams. It is way more complicated. The light switch sends a signal to the Multiplex System Field (MSF) switch. Its the assembly attached to the dash that contains the Four-Way-Flasher switch. That then sends a signal to the SAM cab controller which is located in the passenger firewall. Part of it is behinds the glove box, the other part extends out into the engine compartment. Then the SAM Cab sends the power directly to the fogs lights. Seeing as both now quit: the most common cause is water intrusion into the SAM Cab controller due to a leaking windshield. This will cause corrosion in the wiring harness connectors that plug into the SAM Cab module.
On my western stars, before any truck is put into service, I have a glass company come out remove the windshield then reinstall it with good sealant and a new gasket. Before I did this i would have water pooling on the floorboard and getting the wiring wet behind the dash. They may have fixed this but it gets done no matter what, to depend on the dealer is like waiting for a Martian to come down and fix our cars.
I need last 6 of vin. That's nice the driver's manual was checked, but if more pertinent detail is needed...I need specific information.
