Light switch question

[kid]

Lets see Indiana at 65 mph and 12 mpg, my girlfriends aren't that lucky

[fordman]

if i knew some women on the way i could do that i guess.

[Supermike]

If it helps, once you hit Indiana, you can go 70.

If it were closer to August, I'd just wait for the Street Rod Nationals here in Louisville and park outside the gates with a "somebody please help me" sign.

[fordman]

will work for help?

[Supermike]

That would be a new one, wouldn't it?

[kid]

65 because all three of my trucks have Dana rear ends and all of them have 4.10s.

[ICEMAN6166]

too long of a road trip or i would .
i dont care for that diagram.

[Supermike]

Ok -- here's the latest... I picked up a circuit tester from AutoZone on my way home tonight. I have the panel removed, so I grounded the tester and touched it to the various pins in the harness plug for the dash panel. I got lights on some, not on all. One of the ones I DID NOT get a light on was the blue wire with the red stripe... for the dash lights.

Going down a little further, I checked it against the socket for the cigar lighter bulb. Nothing there...

Moving along to the light switch, I stuck my tester up along the blue wire on the switch. Nothing there. I DID get a light on the others, but not that one.

Moving on to the fuse panel... I turned on the key, and got a light on every fuse BUT the one for the dash panel lights. Tested both sides of the fuse holder. Nothing.

So what gives? I just replaced the fuse. I currently have a 4amp fuse in the panel. The diagram on this site calls for a 2amp, but my owner's manual calls for a 4amp. This is the only fuse on the panel which does not list an amperage. I think that little edge piece is broken off, but not in any way that seems to impact the panel itself.

[fordman]

the power to the fuse comes from the light switch. it has to be a bad connection in the light switch plug. you have already replaced the light switch so that isn't the problem it the connection in that plug.

[kid]

The riveted connections are prone to corrosion caused resistant failures i.e. the metal changes characteristics to the point they can't carry electricity anymore.

Where the Buss Bar inside the fuse holder attaches they used aluminum coated fuse clips and aluminum coated copper or pure aluminum buss bars. They used steel rivets to attach the two items. Bad BAd BAD they corrode from being dissimilar metals.


The light and that means all lights that work without the switch being turned on are fed in a 67 by the Black/Yellow wire no fuse. They are protected by the circuit breaker in the switch.

Trace that wire, my 250 has a problem as that wire is not on the solenoid and I don't have power in my stop fuse anymore. I hate to say it but I might convert my fuse panel to an aftermarket panel that uses AT style fuses.

i have looked at every 67 schematic and then looked into the later years and I never find the instrument panel fuse tied to the light switch for bulb lighting. Inside the switch diagram in some years I did see the pot (variable resistor that dims the light with the hot side tied to the circuit breaker.

[fordman]

yes i guess it could be the fuse holder being corroded but if its not getting power in then it shold be before the fuse holder. unless it is like your thinking and the corrosion isn't leeting the power in. so you may be right about the corrosion factor.

[Supermike]

Holy crap... that's a lot of info to absorb.

Ok... I understand the part about the dissimilar metals and corrosion. However, it seems to me that you are saying that the headlights, cabin lights, and dash panel lights are fed by the Black/Yellow wire and no fuse, and are protected by a circuit breaker in the switch.

But that doesn't make sense, as tracing the Blue/Red Stripe wire from the panel connector down takes it through the fuse block, and the fuse block is marked "dash panel" or something like that.

I guess what I'm saying is that power to the dash lights HAS to run through that fuse... which is returning no juice. So where does that fuse get IT'S power? It has to come from the switch, right? If not, where does the power to that fuse come from? The Black/Yellow wire directly?

Keep in mind... my headlights work fine, as does my cabin lights. It's ONLY the lights on this blue/red stripe wire....

I swear I'd go insane if I were an electrician.

[kid]

The black Yellow wire feeds that fuse. Directly no switch it also feeds the ignition switch and the light switch. Now since all lights dim in the interior go look at the 1969 and you will see inside the switch but still no wires
http://fordification.com/images/schemat ... rging2.jpg

I am just saying what the diagrams show. You do need to solve the no voltage to that fuse problem. In the wiring schematics I never saw the dash lights or the 4 amp fuse. But I saw where the power to the resistor for dimming comes from and that is the Black yellow wire.

in this schematic there is an unmarked fuse feeding the Dash gauges and warning lights.It is a black green stripe and that is the only fuse I can't account for, It is tied to wire 297 that goes to the ignition switch and then to the voltage reg.
http://fordification.com/images/schemat ... gauges.jpg

I am going blind looking at the schematics and they don't show the red/blue wire anywhere except in the dash panel layout as C 19 and 19B
http://fordification.com/images/schemat ... tpanel.jpg

[kid]

I wish I had a 67 here to run a tone test and trace the wires. With Fordifications permission as I feel out the missing wires I will redraw the schematics.

[kid]

Last what I had also meant to say is wire doing into the back of a fuse block does not mean they are fused. since the fuse block has both switched and unswitched power on bus bars it is an easy place to tie off wires. Oherwise the splices and multitaps have to be down at connectors or in mid wire.