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TR4/4A TR4A Ignition Switch Circuit

moe_morin

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I would like to see a schematic of the ignition switch internal circuit. My 67 TR4A switch has 4 positions which I assume are "Acc-Off-On-Start". This arrangement seems at odds with the TR4A wiring diagram which doesn't show "Acc" for the left-most switch position (if that's what its meant for). Also, it doesn't show switch terminal numbers, in particular, the correct "Start" terminal.

Moe Morin
 
My advice would be to use an ohmmeter or powered test light, to determine what your switch does. The factory diagrams weren't always correct, and the switch may have been replaced at some point with one that has different numbers.

PS, oop, you asked for internal. I don't have a diagram handy, but it seems pretty clear to me based on the diagram fragment below:
Off no connections
Acc 1-4
Run 1-2-4
Start 1-2-3 (perhaps 4 but probably not)
 

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