I need electrical help.

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1973Kathleen

1973Kathleen

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I have a 1973 Dodge Dart Sport, and my horn, hazards, reverse lights, and those turn signal thingys on the fenders dont work. I started working on it last November and the horn and fender things worked. what could have caused this?
 
If you do not have, you can download a 73 manual for free at MyMopar.com. Also there, download the aftermarket diagrams in the wiring section. They can sometimes be easier to follow.
 
Check for power at the bulbs/sockets.
neutral safety switch, move shifter slowly while a helper watches reverse lamps
hazzards have their own flasher, swap with turn signal flasher.

Could be separate problems. these things don’t have to big a big complicated fix, but it could be.
 
413 said:
Check for power at the bulbs/sockets.
neutral safety switch, move shifter slowly while a helper watches reverse lamps
hazzards have their own flasher, swap with turn signal flasher.

Could be separate problems. these things don’t have to big a big complicated fix, but it could be.
Click to expand...
I'll try that as well. Thank you!
 
Ground!!! GROUND!!! Ground check all of the Grounds cause if those aren't good you'll forever be chasing your tail
 
I agree with what everybody above has said. I would add that you should get a multimeter, if you don't already have one. Don't make any assumptions as you start to run the diagnosis. It could be a bad connection at the Firewall plugs, a bad switch, bad ground, bad bulb/horn, etc. You need to check everything. When experts like @67Dart273 weigh in, I feel kind of silly adding my two cents worth, but I'm fairly good tracking things down.
Diagnose one thing at a time. For example, start with the horn. Have an assistant press the horn button while you check for power at the horn. If there is power, but the horn does not work, it is either a faulty horn or a bad ground. If there is no power, then the problem is further upstream. Nest I would check the horn relay. Power goes from the relay out to the horns when the horn is pressed. When the horn button is pressed, power will flow to the relay, and if the relay is working, power will flow out the other side of it to the horns. If there is power going into the relay but not out the other side, the relay is bad. If there is no power going to the relay when the horn button is pushed, the problem is further upstream. Time to pull the steering wheel. The power wire going into the horn switch should be hot all the time. The horn switch works by completing a ground and allowing the current to flow, clean the copper ring on the back of the steering wheel and check all connections.
The same strategy can be used for all other items. It is pretty much a bad switch, bad item (horn, bulb, fan motor, etc), bad relay, bad ground or a bad connection/broken wire somewhere. I always start at the item that isn't working and work my way backwards. In fact, it could even be a fuse.
 
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1973Kathleen said:
horn, hazards, reverse lights, and those turn signal thingys on the fenders dont work
Click to expand...

@harrisonm has given you the best method of diagnosing the problem. Unless you see something obvious, you need a strategy that narrows down the problem. If a fuse is blown, then there is a short. If not, then you are probably looking for a break or bad connection,

The wiring diagrams @67Dart273 mentioned are invaluable in figuiring out how items are related. The factory service manual diagram is the most complete and will be the most accurate. So download the service manuals for '73 and look in the electrical sections. The aftermarket diagrams sometimes are easier to read. '73 up diagrams are more difficult to work with than the earlier ones. They are a little bit like puzzles that need to be pieced together. I often redraw the circuit so its easy to understand.

As it happens we can give you a head start.
Here's how the turn signal circuit is wired.
1702130945966.png


B1-18W translates to power for Backup lights 18 gage wire, White insulation.
D1 -18 Bk is power to turn signal flasher 18 gage wire Black.
CE(2) is Connector Engine 2, position B. (there's a diagram of the connector in the book).

A lot more here:
www.forabodiesonly.com

Burnt some Spaghetti!

Hi Folks, I am venturing down the Rabbit hole of wiring at the moment and noticed two fried wires on my bulkhead connection. One is coupled with a black wire, I think it was originally white? The other one is green. 1. Just wondering what might have caused this so I can check and hopefully...
www.forabodiesonly.com www.forabodiesonly.com
1702131663035.png


Note the Horn Relay is on seperate fuse. But as someone noted above, the turn signal switch and more directly the column connector will have wires from both the horn circuits and the horn circuit.


if you follow the above link to the thread "Turn Signals not working, blowing fuse" you'll see how we tracked that one to a short of the back up wire on the transmission case.
 
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Also, pick one thing that does not work and trace it end to end. Often, that will magically fix another problem, or lead you to issues with another problem.

You said your hazards don't work, and the fender turn indicators. But to the turn signals work? Do the FRONT signals work? Do the brake lights?

If the front signals work, that means power is getting through the harness, and that means (for that circuit) that the bulkhead connector is OK. If they are not working, and given the other problems, the bulkhead connector IS A good bet. Actually, you should check it, anyway. Pull the individual connectors off in the engine bay and inspect.

The hazards, remember, you have TWO flasher units, one for hazards, one for turn. You have to find them. If you get into the wiring diagrams in the 73 shop manual, and go onwards AFTER the diagrams, you will find charts there for drawings of connectors, and those give you LOCATIONS.

Here is an example from part of page 8-168. This is showing "CI" series connectors, which means "Connector, Instrument (panel)" and notice that each one has a hint on where to find it, and is drawn so you can see the wire colors you are looking for, and the shape of the connector. Of course you would hope that the hazard one actually has a flasher plugged into it, but you never know

example.jpg
 
harrisonm said:
I agree with what everybody above has said. I would add that you should get a multimeter, if you don't already have one. Don't make any assumptions as you start to run the diagnosis. It could be a bad connection at the Firewall plugs, a bad switch, bad ground, bad bulb/horn, etc. You need to check everything. When experts like @67Dart273 weigh in, I feel kind of silly adding my two cents worth, but I'm fairly good tracking things down.
Diagnose one thing at a time. For example, start with the horn. Have an assistant press the horn button while you check for power at the horn. If there is power, but the horn does not work, it is either a faulty horn or a bad ground. If there is no power, then the problem is further upstream. Nest I would check the horn relay. Power goes from the relay out to the horns when the horn is pressed. When the horn button is pressed, power will flow to the relay, and if the relay is working, power will flow out the other side of it to the horns. If there is power going into the relay but not out the other side, the relay is bad. If there is no power going to the relay when the horn button is pushed, the problem is further upstream. Time to pull the steering wheel. The power wire going into the horn switch should be hot all the time. The horn switch works by completing a ground and allowing the current to flow, clean the copper ring on the back of the steering wheel and check all connections.
The same strategy can be used for all other items. It is pretty much a bad switch, bad item (horn, bulb, fan motor, etc), bad relay, bad ground or a bad connection/broken wire somewhere. I always start at the item that isn't working and work my way backwards. In fact, it could even be a fuse.
Click to expand...
I'm not sure if this helps, but my fuse box is also really hot. you cant touch it without getting burnt.
 
1973Kathleen said:
I'm not sure if this helps, but my fuse box is also really hot. you cant touch it without getting burnt.
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MAN. LOOK into that IMMEDIATELY!!! you may have something drawing a lot of current, you may have wrong value fuses installed (too high amperage) or you may have a bad connection heating up., This can be rust/ corrosion/ looseness in crimps, the riveted connections, or corroded/ weak fuse clips
 
67Dart273 said:
MAN. LOOK into that IMMEDIATELY!!! you may have something drawing a lot of current, you may have wrong value fuses installed (too high amperage) or you may have a bad connection heating up., This can be rust/ corrosion/ looseness in crimps, the riveted connections, or corroded/ weak fuse clips
Click to expand...
I just saw his comment, Del. I am glad you saw it earlier and issued the warning. Could the fuse box get hot if the fuseable link was bypassed/deleted? Hey, @1973Kathleen, @67Dart273 is an electrical expert. heed his warning. If I were you, I would have a way set up to pull the positive battery cable REALLY fast while you are looking into this. Maybe a quick disconnect or just have the battery terminal post(s) pre-loosened. If you start to smell something burning while you are sorting this out, that is NOT the time to be looking for a 1/2" wrench to pull the terminals. Think ahead and be ready.
 
No. There is only two things that cause heat and they might be intertwined. One is too much current being drawn by something, and the other is a loose connection. This can be right at the fuse clip, the rivet for whatever terminal at the fuse clip, or the wire end where the harness connects to the box.

Think bathroom / portable heater. There are larger and smaller ones, some maybe 800w, some up to about 1500 w. They are "safe" on a good tight properly wired outlet, and so long as the cord plug is not damaged. But add some damage, a "well used" loose outlet, maybe an extension cord with the (should be outlawed) molded plastic end connectors, and you have smaller wire in the extension, loose connections at the connectors, and pretty soon you havel warm soft plastic and noticable heat. And of course the larger wattage heaters get hotter.

Perhaps a better example is the headlight switch Every once in awhile you hear about someone with headlights cycling on/ off.

Unless someone has installed large wattage headlamps, the cause is usually either a "weak" breaker built into the light switch, or loose/ corroded connections at the light switch. Either the poor connections are causing heating, or the contacts in the built in breaker have gotten corroded, and heat from poor contact. So the breaker pops, cools down, and tries it again.
 
Another comment about the 73 and later diagrams. Those suck sometimes for tracing and understanding. I actually refer back to the 72 diagrams, which are the last year (for A bodies) of the old line style diagrams. This is also why I often suggest downloading the MyMopar aftermarket diagrams. Unfortunately he has chosen to bundle those into zipped files, so you have to unpack them and figure out which one you need. Remember always that those 2 page 3rd party ones are not always complete as to options, don't show you connector profiles, etc. But the CAN be easier to follow.

The factory ones, 73/ later, are most useful when you use the index before the diagrams, as well as the connector pictorials pages after.
 
67Dart273 said:
Another comment about the 73 and later diagrams. Those suck sometimes for tracing and understanding. I actually refer back to the 72 diagrams, which are the last year (for A bodies) of the old line style diagrams. This is also why I often suggest downloading the MyMopar aftermarket diagrams. Unfortunately he has chosen to bundle those into zipped files, so you have to unpack them and figure out which one you need. Remember always that those 2 page 3rd party ones are not always complete as to options, don't show you connector profiles, etc. But the CAN be easier to follow.

The factory ones, 73/ later, are most useful when you use the index before the diagrams, as well as the connector pictorials pages after.
Click to expand...
I am considering to just say screw it with the 50 year old wiring and just buy all new harnesses. I heard some people say painless wiring was the way to go is that true?
 
If you think looking at a fusebox and tracing wires is a lot of work, just wait until you have to build your own harness from a generic kit.
 
1973Kathleen said:
I am considering to just say screw it with the 50 year old wiring and just buy all new harnesses. I heard some people say painless wiring was the way to go is that true?
Click to expand...

Yes and no. While the Painless wiring is new, it all isn’t color coded and wired the same as a MoPar is. There modeled after a GM. They are very good wiring systems, you just have to know the differences and understand wiring before you jump in. I’ve met a few people that really didn’t know electrical wiring as well as they thought and sold the harness when they couldn’t get it done themselves.

New, year specific wiring harnesses are available from/through Year One and other places. These are excellent reproductions of what your car was made with. I myself having used these found the connectors can be a bit tight and IMO, hard to fully connect to make contact. But they are plug and play as well as a high quality reproduction wiring.

The wiring comes in sections. In example, if you need the tail light wiring, you purchase just that section. I myself needed the wires under my dash in my ‘71 Duster, I purchased just that only. The fuse box was included. Make sure you order the under dash wiring with ether the OEM fuse box or with the blade fuse style you like. Standard or mini blades. If your car didn’t come with the electronic ignition, there are also harnesses that have that mode built into them as well.
 
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