Originally Posted by Danthurs
I would guess a tumbler got jamed. The WD40 may loosen that.
So now the firefighter comes out in me.
If you are going to use WD40 on an electrical component, I would recommend that you remove it from the electrical source, use the spray, wipe it down and let it air dry before applying power back to it. WD40 has a flash point of 131F and certainly is not as volatile as other solvents, but still capable of ruining your day if it ignites. I would recommend that after using the WD40 on the bench, then use a solvent that is made for electrical components like a MAF cleaner spray. That should help remove all remnants of the WD40.