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1994 f350 7.3 turbo - the headlights work, turn signals work, brake lights work but no tail lights? I have replaced the nine pin connector that the headlight light pull switch is connected to as well as the headlight pull switch. It appears to be getting hot and burning up. Does anyone have a cure for this? This has happened three times. Is there a different part? in line fuse? any ideas? Thanks,
Yea, on the '87-'91's if there is a bad ground the plug on the headlight switch will melt, Our 88 has had 3 plugs in the last 5 years. and yet the taillights always worked. but a bad ground will supposedly do that. Not sure if it is true but somebody said that the lights also have a ground that runs to the switch? Don't seem right but who knows.
I have not added a bunch of lights. It has standard trailer hookup with trailer brakes that is all. so you are saying a bad ground....why would it only take out the tail lights? how do you fix a "bad ground"? on the headlight switch itself, it has 9 pins (male end) and one of them looks "burnt" I assume that is the one that controls the tail lights, I have had this apart and replaced enough times that I want a long term fix. Any help is greatly appreciated. thanks,
Do your dash lights work? I have had a blown fuse, (in the fuse block) and no dash or running lights. Sometimes you can have a bulb go bad and cause this, I think the bulb shorts to ground in the base.
the dash lights and tail lights are gone... I have checked the fuse blocks (under the hood and under dash) fuses are fine. the dash and tail lights are the only thing not working... the headlights, blinkers, stop lights, etc all work.... I think I may try a inline fuse and see if that helps, but it is such a pain to get to, I would rather find a long term fix instead of a partial cure. what about the "bad ground" idea.. how do you fix that?
Try Running a new ground onto the tail light wiring from the frame. We had a Heavy Steel deck on our when we had that prob but since we put a box on it has been fine. Then again the wiring was so chopped that I just grounded to the frame when I had the box.
Trailer connector wiring is a good place to get a short.
I think you have a short that is in the tail light circuit, but it is not shorted well enough to blow the fuse. Just shorted enough to raise the current draw to where it is getting the wiring hot enough to melt the connector.
I Have had 6 Ford vehicals (4 trucks 2 cars) with this problem it is caused by Ford using to lite of wireing for the head lights. The current draw heats up the switch and causes the wireing to melt. It can takee out the tail lights the head lights or both. The way to fix the problem is to put relays on the headlights usin direct connections to the battery for the main power to the lights and using the stock wireing to triger the relays. Just a thought
That is a great idea. I went yesterday and got new parts from Ford. New switch and 9 pin connector wiring block. The parts guys told me to get rid off any "extra" lights I have and it will cure the problem. So I am, I only have two small "extra tail lights" on my rollbar which I had forgot about, but maybe they pull just enough to make it get hot.
Next item, last night the key would not turn off all the power? The motor shut off but the radio stayed on? I had to mess with the key and turn it back and forth and turn the steering wheel alot to get all the power off.... any thoughts on this being connected to the headlight switch problem?
How hard is it to replace the ignition? special tools?
Makes me wonder if it is not time for a new truck, I hate wiring, elec problems don't understand them completely, 94 with 150K easy miles..... thanks for the help and let me know your thoughts.
I just went through that with my truck yesterday. I found that the easist way to replace the ignition switch is to drop the steering collum there should be only 2 bolts that hold it up then there are 2 nuts that hold the ignition switch on. Just make sure the rod in in the correct hole on the switch. while the colum is down make sure that the rod is not extremly loose or broken if it is the rod will need to be replaced which is a pain.
with over 30 extra running lights on my 84 and with all my exsperiance with tow trucks over the years I automaticly cut the feed for the parking lights under the hood , then run a thicker wire to the rear junction box ( i make one for all my trucks) the I run a relay under the hood . After all that I have never had to replace a headlight switch again.
I cut off the extra lights, put in a new headlight switch (from ford) and 9 pin connector and we'll see what happens, as for now the lights work fine. But I haven't pull a trailer yet so time will tell, the ignition switch is still a problem that I have to fix but that will have to wait until next weekend