73 valiant no spark from coil
Here are some checking points. Someone was nice enough to send me wiring diagrams for 73, which is the first year for the "new" style diagrams. These can be hard to follow without paper diagrams
The top diagram is the connector coming out of the steering column from the ignition switch
From the top
S2, a no 12 Yellow is the "start" wire, is hot in "start" and feeds through the bulkhead to the starter relay
Q2 a no 12 BlacK is hot in "accessory" and "run" and feeds power to the switched buss in the fuse panel
J2 a no 12 Dark BLue, is IGNITION RUN (IGN 1) and is hot ONLY in "run"
J3 a no 12 BRown IS THE WIRE which feeds cranking voltage to the coil. With the key twisted to start, this should be close to battery voltage, feeds out through the bulkhead, and to the coil + connection on the ballast resistor.
J1 a no 12 Red, is main battery power coming in from the bulkhead
The connections below that are not important at this time
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SECOND DIAGRAM. Look at the top left contact of the ignition switch. THIS IS SHOWN incorrectly. The "START" contact feeding the yellow is NOT connected to the BROWN. THIS BROWN IS a separate contact isolated on it's own and NOT hooked to the yellow.
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BOTTOM DIAGRAM. Look at the bottom right of the page, find J3 14 BR coming in from the right. THIS IS the brown coil "bypass" circuit and this SHOULD be feeding "hot" voltage to the coil + in "start."