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Discussion Starter #1
Today, out of the blue, I turned the key to start my 66 pony. It started cranking and then suddenly (not like a weak battery) it just s th stopped cranking. I ended up having it towed home, but while headlights, horn, instrument panel and cigarette lighter appear to have full voltage, the run and accessory position have no apparent power. I'm thinking it has something to do with the ignition switch, the relay or the starter. Am I on the right track? Where and what should I start checking?
 

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Today, out of the blue, I turned the key to start my 66 pony. It started cranking and then suddenly (not like a weak battery) it just s th stopped cranking. I ended up having it towed home, but while headlights, horn, instrument panel and cigarette lighter appear to have full voltage, the run and accessory position have no apparent power. I'm thinking it has something to do with the ignition switch, the relay or the starter. Am I on the right track? Where and what should I start checking?
Turn key ON, see if voltage appears at the ignition coil (not the grounded terminal). If yes, that suggests the ignition switch is not faulty. Next, have someone turn key to START position, while you check for voltage at the starter solenoid. Note it has two terminals for small wires. One is only energized when the solenoid operates; this sends full voltage to the coil, bypassing the Ignition Resistor. That's the wrong terminal, but no matter, if you get NO VOLTAGE at either terminal, ignition switch is likely the culprit. Or, a bad connection somewhere between the switch and the solenoid. There's a start for you.
 

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Discussion Starter #3
Thanks for the tips! I have new electrodes arriving this afternoon for my multimeter. I'll check it out tonight or tomorrow and let you know what happens.

Today, out of the blue, I turned the key to start my 66 pony. It started cranking and then suddenly (not like a weak battery) it just s th stopped cranking. I ended up having it towed home, but while headlights, horn, instrument panel and cigarette lighter appear to have full voltage, the run and accessory position have no apparent power. I'm thinking it has something to do with the ignition switch, the relay or the starter. Am I on the right track? Where and what should I start checking?
Turn key ON, see if voltage appears at the ignition coil (not the grounded terminal). If yes, that suggests the ignition switch is not faulty. Next, have someone turn key to START position, while you check for voltage at the starter solenoid. Note it has two terminals for small wires. One is only energized when the solenoid operates; this sends full voltage to the coil, bypassing the Ignition Resistor. That's the wrong terminal, but no matter, if you get NO VOLTAGE at either terminal, ignition switch is likely the culprit. Or, a bad connection somewhere between the switch and the solenoid. There's a start for you.
 

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Discussion Starter #4
Only about .018 volts show at either the coil's positive terminal with the key in the "on" position or the relay with the key in either the "on" or "start" position. There is no break in the wire from the switch to the coil (it is a single, non-resistant wire, as I have a flamethrower coil so I have bypassed the pink resistor wire). I double checked all wiring to the ignition switch and don't see any anomalies.

I'm thinking ignition switch. Am I right?
 

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Discussion Starter #5
Ok... It was not the switch. It was the ignition switch pigtail. Once it was changed out, all is now copasetic.
 
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