Headlight switch is driving me crazy

[ProjectResponder]

Ok, here goes...

When I pull out the switch to the first position which should be the parking lights, they energize. Now, when I slowly pull it out to the second position which should be the headlights and parking lights, about half way between the first notch and fully extended, the headlights come on and just another millimeter, the parking lights go off. So it takes a light touch to get the headlights and parking lights to be on at the same time.

This has been crazy now for the last ten years. I've replaced the switch with a new factory replacement, with one from a 1996 salvaged truck. I've replaced the wire bail that connects to the switch. Nothing has made any difference. I'm hoping the tech gurus around here can shed some light on this and help me solve the problem, once and for all.

Thanks

 

[blacksnapon]

Thats going to be one of those research kind of problems. Is it a tilt wheel? Some tilt columns have an issue with the wiring too tight, causing the plugs to pull out of the switch. I've repaired some that the wires pinch in the tilt mechanism. Do you have extra lights wired in to the system?

 

[BKW]

Contact a place that sells/installs auxillary lamps. My guess is, you need a heavy duty headlamp switch. Ford sells these for Econoline ambulances, but there's no listing in the parts catalog for F Series trucks.

 

[bowtiehatr]

is it for the fire truck?

 

[ProjectResponder]

is it for the fire truck?

Yes. That's the one.

 

[ProjectResponder]

Thats going to be one of those research kind of problems. Is it a tilt wheel? Some tilt columns have an issue with the wiring too tight, causing the plugs to pull out of the switch. I've repaired some that the wires pinch in the tilt mechanism. Do you have extra lights wired in to the system?

I don't know how the steering column would come into play, but anything is possible. I do have tilt wheel and I don't have any additional lights on the factory wiring. All of the aux. lights are completely separate.

 

[blacksnapon]

I don't know how the steering column would come into play, but anything is possible. I do have tilt wheel and I don't have any additional lights on the factory wiring. All of the aux. lights are completely separate.

take the trim panels loose, and look at the top. The wiring comes along the top ridge and splits off at/or near the tilt pivot.

 

[ProjectResponder]

take the trim panels loose, and look at the top. The wiring comes along the top ridge and splits off at/or near the tilt pivot.

Why would wiring for the parking/head lights run up the steering column? I know there is some really stupid designing that goes on, I've found plenty of examples. I'll take a look. My question then is how would this affect the actuation of the headlight switch? What should I be looking for?

 

[BKW]

The only wiring in the column is the T/S switch. The horn works off that, the ignition switch is at the bottom of the column and is activated by a slender rod from the lock cylinder. No headlamp loom in the column.


I don't understand what you mean by the statement "replaced the old switch with a new factory replacement, off a salvaged 1996 truck." Does this mean you just put a used switch on?


Replace the switch with a new one..the one from a 1996 may look the same, but is NOT the same. The one from the 1996 may have been bad too.


EDIT: Here's the correct Ford headlamp switch for your truck: E7TZ-11654-C (List price $18.02) Switch fits 1987/1991 F150/350 ONLY.

 

[blacksnapon]

Why would wiring for the parking/head lights run up the steering column? I know there is some really stupid designing that goes on, I've found plenty of examples. I'll take a look. My question then is how would this affect the actuation of the headlight switch? What should I be looking for?

If I remember right, The dimmer switch is there.

 

[econo61]

gotta be in the switch itself. no ifs ands or buts about it!

if you can pull it on all the way, and the park and tail lights go out, it has to be a bad switch.

does it do this when you first install the switch? or does it do it after the switch has been installed for a while.

since it is a fire truck, do you have a bunch of extra tail or running lights installed? if you do you may have to run a relay for them, to much on the switch will burn them up pretty quickly.

 

[ProjectResponder]

gotta be in the switch itself. no ifs ands or buts about it!

if you can pull it on all the way, and the park and tail lights go out, it has to be a bad switch.

does it do this when you first install the switch? or does it do it after the switch has been installed for a while.

since it is a fire truck, do you have a bunch of extra tail or running lights installed? if you do you may have to run a relay for them, to much on the switch will burn them up pretty quickly.

As I stated at the beginning of this thread, I've tried new switches from ford, I've tried switches from salvaged trucks. They all experience the same issue as soon as they are installed. But they work fine on other trucks.

Also, I mentioned that there are no additional accessories on this circuit. I keep all aux. lights on a completely separate circuit with relay controls.

Thanks

 

[mrfixit]

If I remember right, The dimmer switch is there.

That was my first thought when I read his problem; The dimmer switch or the wires in the column chafing. Ford has had issues with that.
Have you tried lighting them on bright to see if they stay on that way?
see, in that "median point" where they both come on, you are actually lighting the headlamps THRU the parking lamp circuit via a psuedo-bridge in the switch.

 

[blacksnapon]

I've replaced dozens of dimmer switches for intermittent operation as well. It's usually the dimmer switch or the wiring.

 

[econo61]

I THINK I GOT IT!

check the fusible links. if i remember correctly, they have 2 powers going to the headlight switch. 1 is fused, the other is a fusible link. if you lost the link for the headlites, you could fiddle with it and make them come on with the park power.

i think it will be at the starter relay, positive side.

 

[ProjectResponder]

I THINK I GOT IT!
check the fusible links. if i remember correctly, they have 2 powers going to the headlight switch. 1 is fused, the other is a fusible link. if you lost the link for the headlites, you could fiddle with it and make them come on with the park power.

Now this makes a lot of sense. I'll get out my wiring schematics and find out for sure. I never would have though about something like this.

mrfixit, yes, the high beams will come on and stay on. The dimmer switch is on the floor, but I'll replace it just in case.

 

[mrfixit]

I've had the floor mounted ones do that. MANY times. Hope it works~!

 

[mrfixit]

Sooooooo..... Did it work?

 

[Blue Goose]

Vince (Blacksnapon) sent me this wiring diagram for you to look at if the truck has a column mounted dimmer switch...

 

[mrfixit]

Uhhh, guys,...

The dimmer switch is on the floor, but I'll replace it just in case.