1991 stock K5, 350TBI, 700R4, etc. Here's the problem, when I turned on the lights the other day I heard something crackling and saw a little smoke coming from behind the light switch, and then quick turned it off to prevent any damage. I took the switch out and ruled the switch out as the possible culprit (I jumpered the wires on the harness that connects to the switch and the headlights(Yellow Wire) work if jumpered to the positive 12V, and the taillights/marker light (Brown Wire) short out if jumpered to positive 12V. Also my dash lights weren't working either. I then took the entire dash out and all looks well behind there. The turn signals/hazards work fine, but the taillights don't work. Therefore I believe I have it narrowed down to somewhere between the switch and the rear of the truck. Question is how do I troubleshoot it down to the culprit? Do you think that the brown wire somewhere is grounding out on something? I'm lost as to where to go from here. One more question is that my check engine light came on and it reads a code 24, which I believe has something to do with the VSS, and to further diagnos this, the speedometer hasn't worked for awhile, so I'm thinking the problem might be a faulty VSS. Any comments or suggestions would be a great help!!