How did my high beams kill my ignition? Options

[87m491]

After doing some bottom side work on my car last weekend (on ramps), and some dash bulb replacements, I went back topside to drive off the ramps (12 hours later) and absolutely no signs of life when ignition key is turned. No generator light, no oil light nada and of course no cranking. No fuses were blown. While the ignition switch hadn't exhibited symptoms of failing I figured I'd swap it out with a spare I had.

I swapped in the spare today. A bit of PITA so I went down an electrical check list before fully buttoning it up. Key on, dash lights check (generator and oil pressure, still stock incandescent bulbs) . Cranked over and instant start, check.

Installed the directional and wiper switch stalk so I can check the functioning turn signals, check. All the illumination LEDs I installed in the gauges this week, check. Running lights, check. Headlights up and check. High beams to check high beam LED, saw the high beam indicator light, heard a relay, click, momentary check, then the dash went dark!
Again, no fuses blown.

Now I am back to the symptoms that led me to think it was the ignition switch. No lights at all on the dash with key on and of course no cranking. Hazards work, 1st position headlight switch items, gauge illumination works, 2nd position headlights do not and fogs do not.

Data point, all of these items worked before the day before my first "dead electrical' experience last weekend. All wiring that I know of is stock.

Looks like 'll be getting friendly with my multimeter once the coming storm passes through the northeast.

Ideas BTDTs welcome.

[87m491]

Thanks, I appreciate the road map. Of course your're likely right that my use of highbeams may have been ancillary and not causal of my current state. I found the current flow diagrams on line which I can follow a bit easier that standard schematics. All I did underneath was tighten the clutch cable and inspect a failed thermostat.

I'm guessing it will be "easiest" to have "power" bypass the ignition
Switch and see where it "stalls" for each affected circuit. (As mentioned some light circuits still have power) But I will go and check major than individual grounds hopefully once the weather passes as the car is currently outdoors. Probably a good idea to replace tranny ground. Newer grounds already installed from battery to chassis and engine.

I did open the high beam relay and while one side of the contact is a bit worn, nothing looked burnt or fused and conventional wisdom seem they rarely fail.

After doing some bottom side work on my car last weekend (on ramps), and some dash bulb replacements, I went back topside to drive off the ramps (12 hours later) and absolutely no signs of life when ignition key is turned. No generator light, no oil light nada and of course no cranking. No fuses were blown. While the ignition switch hadn't exhibited symptoms of failing I figured I'd swap it out with a spare I had.

I swapped in the spare today. A bit of PITA so I went down an electrical check list before fully buttoning it up. Key on, dash lights check (generator and oil pressure, still stock incandescent bulbs) . Cranked over and instant start, check.

Installed the directional and wiper switch stalk so I can check the functioning turn signals, check. All the illumination LEDs I installed in the gauges this week, check. Running lights, check. Headlights up and check. High beams to check high beam LED, saw the high beam indicator light, heard a relay, click, momentary check, then the dash went dark!
Again, no fuses blown.

Now I am back to the symptoms that led me to think it was the ignition switch. No lights at all on the dash with key on and of course no cranking. Hazards work, 1st position headlight switch items, gauge illumination works, 2nd position headlights do not and fogs do not.

Data point, all of these items worked before the day before my first "dead electrical' experience last weekend. All wiring that I know of is stock.

Looks like 'll be getting friendly with my multimeter once the coming storm passes through the northeast.

Ideas BTDTs welcome.