Not getting 12 volts to coil

Not getting 12 volts to coil

Let's start with this.

wrecks said
Yes, I did the voltage drop test from the alternator 'batt' post, and I assume I'm measuring the positive part of the under dash splice circuit, because if I were drop testing the negative part of a circuit , would I have the negative volt meter terminal on the alternator's body's metal body and the positive meter terminal on the battery's negative terminal?

Yes. You can measure for resistance in the grounding with one probe on the battery negative terminal and the other probe on some other ground point. For the headlights, I would probably chose the screw where the headlight wires ground to the radiator support.

wrecks said
the wire with 9 volts under the dash and 10.4 in the engine bay was #16.

let me get this correct.
While someone is turning the key to start, one probe is in the firewall connector at 16?
I'm just a little surprise because that is often sealed making it hard to backprobe.
Same with wire R6 into cavity 18 - the ones I've seen (A-body) are sealed.

wrecks said
# 18 (black) was confusing, as it seemed to go to 0 under cranking.

Are you talking about R6 wire ? The one connected to the alternator?
or are you talking about Q2 on the steering column ?

If R6 is going to zero during start, something is wrong.
If Q2 is goin gto zero during start, that is correct.