Smoking Multi-function Switch

sprowls

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San Mateo, CA
I went out to do the final break in of my black magic brakes on my 2004 LJ this morning and noticed a funny smell and then smoke coming out around the hazard switch. I quickly ran for a wrench to disconnect the battery with visions of the it bursting into flame before I could return. Fortunately it did not. I removed steering column cover and pulled out the multi-function switch. It was a little warm and smelled but otherwise everything looked fine.

I took the back cover off and the circled portion in the pictures is looks discolored from heat, but hard to say for sure. That portion is below the hazard switch. There is lots of what I assume is dielectric grease inside, I wonder if some of that bridged a connection and caused a short.

I don’t know if the unit is aftermarket. The only markings I see are 1408331-112C. The relay is marked made in USA.

Has anyone had or heard of this happening before? I’m assuming it’s a short inside the switch. Could this be a sign of a larger electrical problem?

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The dielectric grease in itself should not cause this type of problem.
The problem may just be too much resistance due to a loose connection which caused arcing.
Are there any melted harness connectors or wires that plug into the MFS ?
Are there any after market lights tied into the circuit OR is there a trailer harness wired in ?
 
No melted wires that connect to MFS. There are after market lights but they are wired directly to the battery and a new switch, no integration with the factory harness. There is also a trailer harness that wa purchased from quadratac and plugs in between the passenger side taillight harness.