Turn Signals Stopped Working

[Daddiojoe]

My '71 has a lot of electrical problems, but I can't figure out why my turn signals have stopped working. Here's the run down:

all bulbs seem fine--everything lights with lights on

hazard lights work fine

flasher works when plugged into the flasher slots on the fuse box, so that would seem to be fine.

I recently cleaned and di-electric greased bulkhead connectors. They all seem to be connecting.

The one thing I'm not sure of is the ground strap for the fuse box. As in there isn't one. The wiring diagram says that there is supposed to be a ground strap, but I can't figure out where it connects.

Any help/suggestions would be appreciated.

Thanks,

Joe

[Jeffc]

do the dash signal lights work?, you said that
the flasher seems to be working.
Brake lights work?

[Daddiojoe]

Dash signal lights work with the hazards on. Not with the turn signals.

I'm assuming the brake lights work. Good question.

Do you have an obvious ground strap on your fuse box? Where does it attach?

Thanks,

Joe

[oneowner71]

Sounds to me like a problem with the turn signal switch in the column. Now what would really be useful is if I could tell you how to find that out for sure without pulling the column apart, but I can't...

[Daddiojoe]

Yeah, I was a little worried about that.



Joe

[Hobcobble]

Clean up all of your grounds first.
John

[Jeffc]

If the flasher seems to be working when the turn signal
switch is on, but nothing works including brake lights, ether there not plugged
in to the right spots, or power from the flasher is not
making it to the TS switch, or the switch is bad.

The dash indcators are pulged into the front signals
wires, you can test for power there, they should be
Light Green and Yellow and have 2 to 3 pulg-ins to
the fire wall side each, single wire from switch
each color, single wire to dash light each.

You can test the brake and
rear signal were they go into the fire wall plug
there Dark Green and Yellow.

The wires are differant lenght to each set of
signal lights, long ones being for the rears
on the signal harness.

Checking power to switch from fuse box at red wire that runs from the fuse box to switch.

White wire is brake peddle feed to TS switch.

[Daddiojoe]

Jeff--

Thanks for the tips. I'll check that red wire. The dash indicator lights light with the flashers on. On my 71 the flashing circuit is separate from the turn signal circuit. I need to make certain that my brake lights are working. I've been assuming that they are.


John--

Which grounds? My schematic shows a ground wire in the proximity of the fuse box, but I'm not finding anything that looks like a ground.

Thanks for your help,

Joe

[sparks]

Sweptlines (and other older Mopars) are notorious for the bodies losing conductivity. Run a seperate groundwire from the taillight plates to frame. I had to, you can't tell once the lenses are in place. I also ran a 10 gauge wire from the negative post to an unused bolthole in the frame. Relying on old bolts to complete the current loop in the truck is a bad idea. Rust is a lousy conductor. Flasher (4 way) and flasher (turn signal) on my 69 use a double unit set-up on the fuse box, but share the same wiring to the rear of the truck. If one unit goes out, the other does as well. Odds are better than even that your wiring harness is getting brittle,and as strands break, you'll continue to lose some electrical functions, even though the harness may look perfect.

Good luck hunting down the gremlins. At least there is only a couple hundred feet of wire in a Swept, not the mile plus found in a late model. A Swept is easy to rewire, a late style (modern plastic fuse) aftermarket fuse box (from Jegs or Summit) is simple to install, connectors are available at any decent parts store in the general electrical aisle. Aviation grade wire is expensive, but the colors match the factory harness, the strands are individually tinned (high corrosion resistance), and the insulation is made of higher quality materials. You can also add in a breaker or relay panel if you wire it yourself.

Fix it once, fix it right. Once the new wires are taped, it will look stock with the hood open. (If you care about that)

[Daddiojoe]

Sparks,

I agree wholheartedly that I ought to rewire the whole truck. I've got the wiring phobia, though. For some reason it doesn't make total sense to me. I've pulled and replaced the head, replaced the whole engine, pulled and replaced the rear end, worked on shocks and brakes, pulled and replaced both intakes and rebuilt the carb on this truck, but the wiring intimidates me. I need to get over that.

Turns out that my brake lights were not both working. One of the filaments on the passenger side light was burned out. I replaced it, but it didn't make any difference with the turn signals.
I checked the red wire and my test lamp tells me it isn't getting power. So, no power to blinker. I went to Auto Zone and bought a new turn signal cam assembly. Hopefully that will fix the immediate problem.

I'll keep you posted,

Joe

[WD]

Rewiring a Swept really is a piece of cake. Any pre-EFI is fairly easy, but Dodges are extremely easy. I rewired 1/2 of my 49 1/2 ton in roughly an hour. Same circuits as my 69 D100. Just no fuse box to deal with (they weren't invented yet). You can get everything you need at Pep Boys plus boat shop or aviation supply house. I like the wires and fuse boxes carried by West Marine. I also use solder-on gold plated wire fittings. They don't corrode, and I don't trust crimp connectors. You should be able to fully rewire a Sweptline in a weekend, at most. I took a rough measurement of the harness on mine. Approximately 250-300 feet of wire, 70 solder-on fittings of different types, 4 1157 type pigtails, 2 headlight pigtails, 1 horn relay, 1 starter relay, 2 ballast resistors (ignition and heater circuits). 2 single contact pigtails. Two packages of heat shrink tubung. I don't like electrical tape, so 20-30 feet of convoluted plastic conduit (parts store type split loom). Other switches from parts store, except headlight, I can't find the right one.

I have to do this slowly due to back problems. Should take a couple weekends to finish off, once I have the money to fix it. I'm deleting the factory harness blocks in favor of marine terminal strips, easier to repair harness damage that way, or to add on accessory circuits later on. My truck is a heap, but it's going to work right. I'll fix the cosmetics later.
-WD

[Hobcobble]

Joe,
I was referring to the body-to-frame grounds, the
cab-to-box ground and the lamp housing-to-body [or
frame] grounds. Every spring, I have to clean up my
front lamp grounds on my '61 or I have troubles. I
suggest this step first as its the easiest to take
care of and is the root cause of a lot of electrical
headaches. If its not the grounding, take JeffC's
advise from his post.
John

[Jeffc]

Sparks,


I checked the red wire and my test lamp tells me it isn't getting power. So, no power to blinker.

Joe

Joe, check the fuse, there should be a signal fuse
supply to the red wire, if fuse is good clean both
sides and check power supply to fuse clip.....
may be the problem...

[Daddiojoe]

Jeff--

Thanks for sticking with me on this one. The fuse is fine, so I'll check the power supply to the fuse clip as suggested. I'm lousy at reading schematics and thought that the electricity was flowing the other way--from the red wire through the blinker to the fusebox.

Appreciate your clearing that up.

Joe

[JimE]

Not to put another stint in your artery, a major area of concern. Sorry just wanted to get your attention. The stop light switch with a white wire going to the flasher and a red to battery, has alway been a major problem when you think your turn signals or brake lights are acting up. Jim

[Daddiojoe]

OK, I think I'm closing in on this one...

There wasn't any power to the fuse. But if I run a line directly from the battery and put it to the top of the fuse, I can make the turn signals flash.

So here's the BIG QUESTION--does this mean that the turn signal cam is the problem? Or is it the power source to the turn signal cam?

I'm having trouble reading the schematic and figuring out what the power source to the cam is.

Thanks for bearing with me,

Joe

[cowboy]

Joe , the trouble is in or before the fuse block , if theres no power to the fuse , trace the wire to the plug in the firewall & then to the out side power source , power has to go through the fuse to get up to the t s cam

[Jeffc]

If you are getting power to both sides of the fuse
then it is the wire from the back of fuse block to the red wire supply to switch.


If your are getting power to at least one side of the
fuse, then check that fuse, it should be passing volts
if good, if you replace the fuse and it still does not
pass volts to the other side, clean the fuse holders
on ether side and try again (if this fails you can do the next step below).

If you are not getting power to ether side of the fuse
here is what I would do, don't use the fuse block,
instead use the red wire that supplys the turn signals
and wire a new wire from it to the switched power on
the back of the alt gauge, there is a buss bar on the back with male connectors and it is switched power, just be sure to use
a in line fuse. You should be able to get a inline
fuse with pigtails (10 gauge wire pigtails) at Radio Shack or auto parts store,
just splice it into your wire and get a female to plug into the buss bar and your done....

I do not think you have a problem with the switch at all.
All the cam really does is hold everything in place on
the switch and returns the switch to neutral.

[Daddiojoe]

I've been looking at the schematics again and what you all are saying makes a lot of sense. I'll have some time to mess with it this afternoon.

Let you know how things go and thanks,

Joe

[Daddiojoe]

AFter all that, it was just the fuse holder needing to be cleaned up.

Thanks for the help and support. Someday I will rewire the whole thing. There's other stuff to take care of first.

Gratefully yrs,

Joe