Tail lights
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Mountain Pass
Joined: Aug 2016
Posts: 173
Likes: 0
From: Meridian ID
Tail lights
So the project for this weekend will probably be tail lights. I have several other things to do but I'm not going to tear anything apart as the kid is borrowing the other vehicle. I've learned my lesson 
have a backup 
Anyway, the tail lights.
Running lights work fine.
Brake lights work fine.
Turn signals work most of the time. Sometimes they won't flash at all, but most of the time the passenger side works fine but the driver side will flash until I step on the brake pedal enough then it quits flashing. Notice I said enough, if I am just barely on it the tail light still flashes.
Any guidance of what to look for? Remember you won't insult me with assuming I know nothing because I don't!
I have the wiring diagram and such.
I have a class 3 receiver hitch and a 7 pin plug-in for trailer lights and a brake controller. Obviously the farmers who originally owned the truck pulled a trailer of some sort. Don't all farmers have multiple trailers? Anyway.
I intend to gut any trailering wiring as it looks terrible and I need to start fresh so I'm looking for recommendations there as well.
Go!
have a backup Anyway, the tail lights.
Running lights work fine.
Brake lights work fine.
Turn signals work most of the time. Sometimes they won't flash at all, but most of the time the passenger side works fine but the driver side will flash until I step on the brake pedal enough then it quits flashing. Notice I said enough, if I am just barely on it the tail light still flashes.
Any guidance of what to look for? Remember you won't insult me with assuming I know nothing because I don't!
I have the wiring diagram and such.
I have a class 3 receiver hitch and a 7 pin plug-in for trailer lights and a brake controller. Obviously the farmers who originally owned the truck pulled a trailer of some sort. Don't all farmers have multiple trailers? Anyway.
I intend to gut any trailering wiring as it looks terrible and I need to start fresh so I'm looking for recommendations there as well.
Go!
Thread Starter
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Mountain Pass
Joined: Aug 2016
Posts: 173
Likes: 0
From: Meridian ID
Nope, bulbs are all good and flasher is good. This is a problem that has been ongoing since I got the truck. Was exacerbated by having my brother in law "help" fix them.
I'm not going to rip anything out until I have everything up and running properly. Then i cut out what's left over
I'm not going to rip anything out until I have everything up and running properly. Then i cut out what's left over
Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
My first thoughts are to make sure all the bulbs are good, especially the dual-filament types and make sure one of the filaments didn't break and fall down onto the adjacent one, this can cause really weird problems when that happens.
At the same time, make sure the bulb sockets are clean and free of corrosion and their ground connections are good.
User-added trailer wiring done in a haphazard fashion has been known to cause all kinds of weirdness.
After all of that, including the flasher, next place I'd be investigating is the turn signal switch. But make sure the base infrastructure is good, first.
At the same time, make sure the bulb sockets are clean and free of corrosion and their ground connections are good.
User-added trailer wiring done in a haphazard fashion has been known to cause all kinds of weirdness.
After all of that, including the flasher, next place I'd be investigating is the turn signal switch. But make sure the base infrastructure is good, first.
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
The 4 way H/D flasher can be used in place of the T/S flasher (and was with trailer tow), but the T/S flasher is a "weak sister" should not be used anywhere else.
1980/86 parts catalog pic shows that the T/S flasher plugs into the fuse box. Couldn't find the other, but on 1967/79's, it fits into a bracket located behind the instrument panel, adjacent to the cluster.
FTE Legend
Joined: Nov 2015
Posts: 30,935
Likes: 4,123
From: Angier, NC
So the project for this weekend will probably be tail lights. I have several other things to do but I'm not going to tear anything apart as the kid is borrowing the other vehicle. I've learned my lesson have a backup
Anyway, the tail lights.
Running lights work fine.
Brake lights work fine.
Turn signals work most of the time. Sometimes they won't flash at all, but most of the time the passenger side works fine but the driver side will flash until I step on the brake pedal enough then it quits flashing. Notice I said enough, if I am just barely on it the tail light still flashes.
Any guidance of what to look for? Remember you won't insult me with assuming I know nothing because I don't!
I have the wiring diagram and such.
I have a class 3 receiver hitch and a 7 pin plug-in for trailer lights and a brake controller. Obviously the farmers who originally owned the truck pulled a trailer of some sort. Don't all farmers have multiple trailers? Anyway.
I intend to gut any trailering wiring as it looks terrible and I need to start fresh so I'm looking for recommendations there as well.
Go!
have a backup Anyway, the tail lights.
Running lights work fine.
Brake lights work fine.
Turn signals work most of the time. Sometimes they won't flash at all, but most of the time the passenger side works fine but the driver side will flash until I step on the brake pedal enough then it quits flashing. Notice I said enough, if I am just barely on it the tail light still flashes.
Any guidance of what to look for? Remember you won't insult me with assuming I know nothing because I don't!
I have the wiring diagram and such.
I have a class 3 receiver hitch and a 7 pin plug-in for trailer lights and a brake controller. Obviously the farmers who originally owned the truck pulled a trailer of some sort. Don't all farmers have multiple trailers? Anyway.
I intend to gut any trailering wiring as it looks terrible and I need to start fresh so I'm looking for recommendations there as well.
Go!
My first thoughts are to make sure all the bulbs are good, especially the dual-filament types and make sure one of the filaments didn't break and fall down onto the adjacent one, this can cause really weird problems when that happens.
At the same time, make sure the bulb sockets are clean and free of corrosion and their ground connections are good.
User-added trailer wiring done in a haphazard fashion has been known to cause all kinds of weirdness.
After all of that, including the flasher, next place I'd be investigating is the turn signal switch. But make sure the base infrastructure is good, first.
At the same time, make sure the bulb sockets are clean and free of corrosion and their ground connections are good.
User-added trailer wiring done in a haphazard fashion has been known to cause all kinds of weirdness.
After all of that, including the flasher, next place I'd be investigating is the turn signal switch. But make sure the base infrastructure is good, first.
For the "tail lights" I would start up front at the main harness plug to see if you have "tail light" power there and if so work your way to the rear.
There are TWO different flashers, one for the turn signals, t'other for the 4 way flashers. The 4 way flasher is a heavy duty unit, has a louder CLICK
The 4 way H/D flasher can be used in place of the T/S flasher (and was with trailer tow), but the T/S flasher is a "weak sister" should not be used anywhere else.
1980/86 parts catalog pic shows that the T/S flasher plugs into the fuse box. Couldn't find the other, but on 1967/79's, it fits into a bracket located behind the instrument panel, adjacent to the cluster.
The 4 way H/D flasher can be used in place of the T/S flasher (and was with trailer tow), but the T/S flasher is a "weak sister" should not be used anywhere else.
1980/86 parts catalog pic shows that the T/S flasher plugs into the fuse box. Couldn't find the other, but on 1967/79's, it fits into a bracket located behind the instrument panel, adjacent to the cluster.
Dave ----
Moderator
Joined: Jan 2001
Posts: 56,992
Likes: 2,741
From: Virginia
Pressing on the brake and it quits flashing is not a normal failure mode. Sounds like the wiring is not right back there. I bet you take the trailer wiring out and your problem will go away.
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Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
It's on the back side of the fuse box (as Fuzzy said above).
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Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
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From: Simi Valley, CA
Since you're still awake, grab a flashlight and jog around the block, take a few selfies and post 'em so we can see examples of a running light.
Some people use the weirdest terms to describe simple things. The only running lights I can recall are athlete's carrying the Olympic Torch.
Some people use the weirdest terms to describe simple things. The only running lights I can recall are athlete's carrying the Olympic Torch.
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
I'm familiar with motorboat running lights, but the term running lights shouldn't apply to vehicles, as it's confusing.
Sign on London streets: No Parking on the Pavement which the Brits call sidewalks.
Great Britain and the United States, two nations separated by a common language. -George Bernard Shaw.
The Model T was the perfect family car. It had a hood for father, a cowl for mother and a rattle for baby.
Thread Starter
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Mountain Pass
Joined: Aug 2016
Posts: 173
Likes: 0
From: Meridian ID
So to add to this fray...
I changed the turn signal switch last year and this fixed my problem. Then one tail light quit working, that's when the brother in law helped, never thought to check function with the brakes applied.
I'm thinking a bad ground or connection might be the problem.
Number Dummy are you saying I can use the listed hazard flasher in place of the "weaker sister" turn signal flasher?
While we're on it what do we call the "non-headlights" that will activate the secondary filament of a dual filament bulb when the headlight switch is in the "pre-headlight" position?
"Ancillary lights?"
I changed the turn signal switch last year and this fixed my problem. Then one tail light quit working, that's when the brother in law helped, never thought to check function with the brakes applied.
I'm thinking a bad ground or connection might be the problem.
Number Dummy are you saying I can use the listed hazard flasher in place of the "weaker sister" turn signal flasher?
While we're on it what do we call the "non-headlights" that will activate the secondary filament of a dual filament bulb when the headlight switch is in the "pre-headlight" position?
"Ancillary lights?"
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
Dealers installed the H/D flasher in place of the "weak sister" that has a mild click, difficult to hear when people are hard of hearing.
The weak sister and the H/D unit are round, look very similar with two prongs.
Thread Starter
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Mountain Pass
Joined: Aug 2016
Posts: 173
Likes: 0
From: Meridian ID
Absolutely, FoMoCo used the 4 way H/D flasher for the turn signals on Camper/Trailer Specials.
Dealers installed the H/D flasher in place of the "weak sister" that has a mild click, difficult to hear when people are hard of hearing.
The weak sister and the H/D unit are round, look very similar with two prongs.
Dealers installed the H/D flasher in place of the "weak sister" that has a mild click, difficult to hear when people are hard of hearing.
The weak sister and the H/D unit are round, look very similar with two prongs.
I will like using the heavy duty version, I'm at about a 50% hearing loss.
I will try this before anything else.
Tuned
Joined: Oct 2008
Posts: 387
Likes: 2
From: Las Cruces NM
Back on Long Island NY, we always called them parking lights as well. I never heard the term 'running lights' in reference to a car until the 'daytime running lights' terminology came about after some safety study. With trucks (not pickups), running lights we always called the cab tops and side markers.
But I'm a bit old. I remember when people actually only used fog lights - get this - in foggy weather...
But I'm a bit old. I remember when people actually only used fog lights - get this - in foggy weather...