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TR4/4A Headlight switch wiring. Please help

shoopal

Jedi Trainee
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65 TR4A. Light switch on stalk. 5 wires coming out of the switch harness. There are 3 heavier gauge wires , A Blue (U) a Red with a green stripe (RG) and a Brown with a green stripe (NG).
When in off position no wires connect. When in middle position NG and RG connect. In the top position NG connects to both U and RG. There are also two other wires of a smaller guage, a brown and a blue/white stripe which don't seem to be connected to anything in any position whatever.
I assume that NG goes to the fuse box feeding from the Ignition switch. RG feeds the other fuse which goes to the marker lights and instrument gauges lamp rheostat. The U goes to the dimmer switch which feeds the headlights.
The question is where do the smaller wires go? They don't seem to have any purpose.
Help please
Al Shoop
 
Offhand, no guess on the smaller brown wire, but it must provide power for something? The blue w/white stripe wire could go to the other such wires on the high beam circuit; it is for the "flash-to-pass" function, something often NOT connected originally on US-spec. cars depending on local laws.
 
You are probably right. On close inspection, I see that the smaller wires go to contacts inside the switch which have no mates. Looks like it was set up for something to happen if one pulled the stalk. Maybe like a high beam flasher or somesuch. The spring would indicate that the plastic base would be moveable but it is not.
Update. I have two switches. One from a 65 and one from a 67. The pictured switch is the spare that I was playing with. Not sure which one it is but I think it is the 65. The installed switch stalk will pull and connects the two small wires.
The wiring diagram in the manual shows the 3 wired setup, the Dan Masters diagram (attached) is a bit confusing but does show the 5 wire setup. It's getting more clear how to wire this up. My only question is why did they use a smaller wire for the headlight flash (short term pulses?) vs the larger wires from the dimmer switch (on for long duration?)
Well, onward.
By the way, if anyone wants the pictured switch, free plus shipping costs (good condition except the stalk chrome is pitted up)
 

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