Hot resistance wire

[myblue67]

So tuning up car after new points etc and engine died. Was doing other things and forgot to turn key off for maybe 5 minutes when I noticed wiring harness melting... Damn I said! The resistance wire was super hot? I know what it's supposed to do but wouldn't think it would get that hot no matter how long key left on. Any thoughts?

[L78 steve]

Key on, points open, not a problem. Key on, points closed (making contact) makes the + wire hot.

[myblue67]

Thanks Steve, makes sense but seems a bit risky way to design a circuit. Seems like a a fuse or breaker should kill it before it catches the car on fire.