Headlamp & Horn

[gunbunny]

Okay, I'm taking the lazy route for a second and asking here.
Wiring diagrams give me a headache.
75 Dart SE, turn the headlamps on and no horn.
Turn them off, horn works great.
Does the horn go thru the headlamp switch and if so why?

I rarely drive the car, and when I do, seldom at night. Drove it the other night and of course Bambi want to walk out in front of me and when I laid down on the horn, nothing.

 

[67Dart273]

This is likely something like a poor column ground. No the horn does not go through the headlight switch. If you are going to do much in the way of electrical you are going to HAVE to learn a bit about diagrams I admit, the 73/ later diagrams can be a PITA. I use them in combo with the simplified 2 page ones at MyMopar. Those are not detailed as per OEM and leave some things out. But they DO provide a line drawing that can be easier to follow

I would start by accessing the horn relay. The horn button is normally small black. Pull that off or back probe the connector and see if the voltage goes to ground when operating the horn button. Then turn on lights and check same. Also try grounding that terminal with a jumper wire and see if symptoms change

 

[gunbunny]

This is likely something like a poor column ground. No the horn does not go through the headlight switch. If you are going to do much in the way of electrical you are going to HAVE to learn a bit about diagrams I admit, the 73/ later diagrams can be a PITA. I use them in combo with the simplified 2 page ones at MyMopar. Those are not detailed as per OEM and leave some things out. But they DO provide a line drawing that can be easier to follow

I would start by accessing the horn relay. The horn button is normally small black. Pull that off or back probe the connector and see if the voltage goes to ground when operating the horn button. Then turn on lights and check same. Also try grounding that terminal with a jumper wire and see if symptoms change

Ground makes sense. I did notice when I pushed the horn, the dash lights, that were already dim, got worse.
Come to think of it, the dash lights would only work in one place on the dimmer.
I may pick up a new switch when I'm at Carlisle. But I'm start with the relay and see what happens.
I'm sure I'll be asking more questions in a week.