how to test ign/light switch

1930artdeco

Well-known member
Ok, so I have the Ign/headlights switches out now how is the best way to test them? I don't have a key yet for the ign. and the manual wasn't super helpful in testing either switch. Or I flat out missed the page (probably a good chance on that). Also, on the ign switch, is the plastic body supposed to be loose? I can rock it a bit, doesn't seem right to me.


Thanks,


Mike
 
Use an ohmn meter, attach one lead to the input post and the other to the output post and check for continuity when you activate the switch
 
Headlight switch wiring image below.

Ignition switch is pretty basic. A large Yellow battery power wire, a Red/ blue on the Start terminal, a Red/ green wire to the ballast resistor and/or plus (+) terminal of the ignition coil and Black/ green wires to the Gen & Oil lights on the Ignition terminal. And the Accessories on their terminal.

A full wiring schematic diagram at this link...
http://www.oldcarmanualproject.com/tOCMP/wiring/5765wiring%20diagrams/fordindex.htm
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Use an ohmn meter, attach one lead to the input post and the other to the output post and check for continuity when you activate the switch
In other words, the needle of the ohmmeter will go to zero (meaning zero resistance) when two poles inside the switch are connected, and the needle should read maximum resistance when the switch knob is shut off.
That would work for the headlight switch, but you will have to have the key for the ignition switch to test it using this method.
I have had one of these '50's Ford ignition switch with the bakelite module in the back loose in the pot-metal housing. If you can get some wood blocks to set the switch on and a piece of heavy-wall pipe just the right size to fit the chamfered part of the back of the metal housing and pop it with a hammer, that will tighten it up. That does not guarantee that the switch is good but worth a try if you wanna take a chance on using what you have.
 
Thanks guys, That is what I was looking for. I will drop the switch off at a lock smith to get a key made. Then I will start testing and asking many, many, many, many more questions-some of them will be dumb as I am an electrical idiot-readily admit it.


Mike
 
Ok, looks like the HL switch is working as it should. Is there a way to lube it? I can spray it down with ‘corrosionX’ which is supposed to be an electrical contact lube. As for the reostat just find the output and see what the ohms do?

Thanks,

Mike
 
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