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temporary ignition switch

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S

sp53

Yoda
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I have question about wiring in a temporary ignition switch. I have an old generic switch that has the four lugs on back: acc, bat, ignition, and start. I have one wire from battery side of the switch to the battery. I have one wire to the ignition side of the coil and switch. And one wire from the start side of the switch to the solenoid. My problem is I cannot get the start side of the switch to engage. Do I need a second wire? The switch turns on and off fine and I can push the button on the solenoid to start the car so the ignition side works, but when I turn the key to start nothing happens. My first guess was that the solenoid was defective, but I tried another one and I have the same problem. Why when I turn the key to start the solenoid won’t activate? I just cannot see it. I thought the switch was bad, but if I turn the key to start and check for continuity from the battery side of switch and start side of the switch there is a connection.
Steve
 
Hmm, seems to be a disconnect there. The 3 wires as you describe should be all that is needed.

I would connect a voltmeter or test lamp between a good ground and the start contact on the switch. Turn the switch to 'start', you should see 12v on the voltmeter. If so, the problem is somewhere between there and the solenoid, so repeat the test with the lamp/meter on the side terminal at the solenoid.

If no 12v, then repeat the test with the meter/lamp on the battery terminal of the switch. If you still have 12v there in 'start', the switch is bad regardless of your continuity check.

See, most continuity checkers will report anything less than a few ohms as continuity. But a few ohms won't pass enough current to activate the solenoid, it needs to be a few tenths of an ohm in order to actually work. Testing in-circuit as I've described is the best way to not be fooled (in this case).
 
When you push the button on the solenoid to start the car, you are <span style="font-weight: bold">mechanically</span> closing the solenoid contacts for the starter. The coil in the solenoid could be toast, but pushing the button will crank the starter.
 
:iagree: Also, the body of the solenoid must be grounded for the coil to work, but not to use the pushbutton on the back. You might try temporarily grounding the coil just to see what happens, in case the screws aren't doing the job for some reason (like paint between the clips and body).
 
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