ignition switch ???

Bulldozer said

74 charger , seat belt thing has been bypassed. trying to get 12v out of the ignition wires at the ballast connectors for a GM module. the blue wire has just about 12v in the run position , the brown about the same in crank position, but when I jumper them together , the voltage drops to around 7.5-8v . is this a short or huge draw in the switch or another possibility? or is this normal ?
also , if I connect the blue/brown together and hook them up at the + on the coil and disconnect the brown wire from the ballast connector, it sparks and I get 12v again.
thanks

Click to expand...

How does the ballast figure in? It should be bypassed/ removed.

The connection you are testing there has more load, normally that is, than just the ignition. It also junctions and feeds to the alternator field, the VR "ign" terminal, and possibly some underhood smog devices. EG electric choke, distributor retard, idle solenoid, and some other "junk."

IT MIGHT BE that your bulkhead connector is loose/ corroded and that you wiggled it just enough to "unmake" the poor connection. I'd start by pulling that apart and inspecting and repairing.