72 C20 No Electric

[jeff71]

I have no electric at all on a 1972 Chevy C20. Unfortunately, I hooked a battery charger up the wrong way for about 5 minutes. It did start and run several times after I corrected the problem and finished charging the battery, but after a few successful starts, it went dead. I have followed the steps provided by Zeke's Garage on an earlier post called "No Electric" from 2011. This included: I have tested for voltage at the battery, side junction, positive post on the alternator and the block on the firewall. I have voltage on all those. I think this proves that there is not a fusible link that has gone bad. Let me know if that is wrong. Next, I tested the power wire coming into the cab from that firewall block, and then I tested voltage at the power wire going into the ignition switch. For these checks in the cab, I used the dimmer switch on the floor as the ground. Those two checks also provided voltage. (I have a new ignition switch.) Next, I thought I would check the ignition wire for voltage with the switch set to crank the starter (pink wire). I took out the ignition fuse from the fuse box, clipped my positive from my tester to where the pink wire comes into the fuse box, and clipped my ground from the tester to the dimmer switch. When I turn the ignition switch to the cranking position I get no voltage and the tester goes into continuity mode (which is what it was designed to do if there is no voltage). I do get a beep, so there is continuity. I am wondering now what my next step should be. I think if everything was working properly, I would have gotten a voltage reading and that makes me think that I need to inspect that pink wire, which means pulling out the dash panel to get to its full length. But I would like the opinion of someone with better knowledge than myself.