Chrysler Repair: Headlight switch 1991 Dodge Dynasty, dodge dynasty, variable voltage

Question
Roland for about a week when i have my headlights on I get a
smell of electrical burning I removed my headlight switch and plug that goes on the switch was melted the wires are ok but the plug is not what could cause this all lights were working  

Answer
Hi Billy,
There are two plugs, one with two wires (a ground and a illumination lamp variable brightness output) and then multipin plug which uses 7 of the pins on the plug. If the 2-wire plug was involved then I would suspect the insulation between the two wire was compromised and produced a partial short that heated up the plug. If it is the multi-wire plug, that one has no ground wires but there is one variable voltage wire (yellow/black) for the adjustable dash illumination which would have some less that 12v on it so a partial short in the plug would cause heating which would melt that plug. The other possibility is that the variable resistances in the body of the switch which creates the variable voltage of the adjustable illumination and those resistors heated the switch contacts connected to the resistors which then heated the contacts in the plug and that heated the plug rubber. It is now approaching 20 years of such day to day heating so it is not surprising that rubber has been deformed. With that deformation could have producted melting and consequent partical shorts which made for quite hot conditions and the smell of burnt rubber. I would go to wrecking yards to find a replacement plug which you could splice into the harness  after removing the melted plug. When you have that ready, then use the switch for a few trips to verify that you have eliminated the shorts and consequesnt burning/melting.
Roland