On my 73 mustang I noticed a short delay when I pulled the switch out for my headlights when I left my house the other day, but didn't think anything of it until when I tried to leave the place I was at I got no response from the switch.

So this is where im at, I figured it was the switch that went bad so I bought a new one, only like 15$ and nothing. All other lights work fine it is just the ones that run of the light switch. (front headlights, Parking Lights, and Dash Lights). I spent 5hrs yesterday messing with it and nothing worked.

Could anyone help me out with more suggestions?

 

there is power running to the harness, via yellow wire which is correct. I can not find the issue. I believe that the ground for the headlights is also on the radiator supports and the grounds are fine, I even sanded them.. PLEASE HELP ME!

 

Have you tried to do a search for related threads. There has been many posts on this same problem.

 

Last problem like this on the forum ended up being the DIMMER SWITCH, I missed the call on that one, kind of forgot about them.... not this time though..

 

Yes I have tried related threads, I have replaced the dimmer switch and the headlight switch. I don't know where to start my troubleshoot, I have checked all I can think of.

One thing very odd today was that when I was testing the power at the headlight harness, while I was plugged to positive with my tester, the two sides light up (suspected ground) but the top one did not (suspected positive). This was on the passenger light, when I plugged in the driver side light the top one did light up leading me to suspect that it is grounding out some where.

The parking lights both read all 3 wires ground also.

Anybody know where I should start???? PLEASE

 

have you checked the fuses? I had a simular problem and it ended up being a 2 amp fuse

 

There is no fuse for the headlights, the switch contains an automatic circuit breaker.

Are you getting power to the headlight switch?

 

Yes, the Yellow wire, Hot, Does have power

 

On a 66 switch, there are TWO hot wires, one for the parking/tail lights and a second for the headlights.

Can't say that this is the same on a 73.

 

Have you done anything to the car lately? I would take a look at the bulkhead connection. (where the harness goes thru the firewall) Unplug it and plug it back in.