Vintage Mustang Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
103 Posts
Discussion Starter #1
My headlight circuit and fried, along with melting the headlight switch, so I replaced the wiring harness to the headlights, as well as the switch. I didn't replace the dash harness, as only one wire was fried -- which I replaced to the firewall.
I had to insert the wires into the new headlight switch.
The new headlight switch came with the car -- the box is labelled "Mustangs Unlimited" PYH65, and SW441-02, "Headlight switch 65/68 Mustang" 02-AE-11-AC-AA

I also wired in one of the pre-wired headlight relay harnesses.

I just now put in the headlights, and they do NOT work!
In fact, the front parking lights do not come on either.
I have fiddled with the switch over and over. AND the shaft on the headlight switch sometimes pulls all the way out, AND sometimes, after I turn the knob round and back, the knob will only pull out one click. I then have to turn it all the way in one direction or another, and then it will pull out 2 notches, OR pull all the way out.

TWO QUESTIONS:
1) Why is the knob and shaft pulling all the way out, or just limited to one click, etc.? Is this a defect in the switch or am I not installing it correctly?
2) Is there more than one way to wire in the light switch for a 1966? I transfered the wires to the new switch exactly as they were on the old one. Did they change switch circuitry for 1966?

Any ideas?
Thanks.
 

·
Registered
Joined
·
128 Posts
Your headlight switch should have two pull-out positions. The first is for parking lights only and the second is headlights & running lights. The push button on the switch is only used to remove the rod assy out of the switch. Turning the switch should go from full left (dim dash lights) to bright dash lights then another click to full right for dome light. I don't believe the 66s came with a headlight switch relay. My 66 wiring diagrams don't show any relay so yours is probably an add-on and may be the cause of your problem (unless the entire headlight circuit has been modified).
 

·
Registered
Joined
·
103 Posts
Discussion Starter #4
Woodchuck - for some reason, the shaft will stay in there very securely, but after I turn the knob to dim or brighten the dash, it will pull right out.
ALSO, like I said, sometimes I can pull it out the 2 clicks (parking and then headlights), but other times, it will only come out ONE click, no matter how much I fiddle with it.
Then, after I turn the knob clock or counterclockwise, it will pull out 2 clicks OR it will come all the way out.
Yah, I have spent more than 20 minutes messing with it -- repeating the same thing over and over, hoping that something will magically change.

I'm thinking I better just order another switch, although this one was brand new, still in its box.

Travis - the relay circuitry is the plug and play harness that you buy on line. Very simple to install, and difficult to screw up.
 

·
Registered
Joined
·
103 Posts
Discussion Starter #9
Am ordering another switch. Hopefully the problem is NOT with the shaft/knob... but, no other way to check.
 

·
Registered
Joined
·
202 Posts
I had an issue like that in my 64, new knob and headlight switch but would pull right out.
Contacted the supplier and was told to take a little off the length of the taper of shaft and re file to shape, a few mm. It worked. It was a Scott Drake part as well.
 

·
Registered
Joined
·
103 Posts
Discussion Starter #11
Tony - good info, thanks. I am awaiting another switch, and if that shaft pulls out again, I'll give it a try shortening the shaft. It would make sense - shaft being just slightly too long so that it does not solidly lock in. Will shorten/taper it a mm at a time.
Good info , thanks for chiming in!
 
1 - 11 of 11 Posts
Top