Turn signals not working, blowing fuse

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Don't concentrate on the turn signals!!! Find out what all is on that fuse, someone posted a chart earlier.........

Radio
Back up lights
Dash mounted reverse indicator (if used)
Stop lamps
Turn signals.

1...Pull the flasher
2...Remove left kick panel and separate the connector to the rear
3...Get under the car and pull the connector off driver side of the transmission. This is three wire if automatic, and this will disable your neutral safety switch. If you need to crank the car you'll have to go up to the start relay, remove the dark colored "push on" wire (flag terminal) and ground that terminal with a clip to get it to crank with the key

4...RADIO.....what do you have, factory, hacked, aftermarket? Locate the radio connector. If you look "on past" the diagrams in your FSM there are charts there to identify the connectors. Look at the radio connector and see what condition it's in, hacked, bare, etc.

Now see if you can replicate the problem with all that disconnected

It might pay to pull the fuse box down and just examine it. Added wires? Hacked splices? Junk/ loose/ rust/ etc, just look it over good

FUSE CLIPS !!!! Look at the clips holding the fuse(s). Rusty, corroded, loose fuse clips make HEAT (poor connection) This can cause a fuse to blow because HEAT is actually what does blow a fuse...normally too much current going through the fuse heats it and melts it. A loose clip heats the fuse and........................
 
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...................You say cavity two........maybe we are on the wrong track.............

I had to re re re download the 73 FSM, my other computer is temporarily AFU

Radio connector, page 8-168 of the 73 Dodge Dart section from FSM, MyMopar

radioconn.jpg


Fuse panel. This gives you wire numbers

fuse.jpg
 
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67Dart273 said:
Don't concentrate on the turn signals!!! Find out what all is on that fuse, someone posted a chart earlier.........
Click to expand...
Heater
Radio
CE2 (B) to Reverse lamp switch
Flasher unit - turn switch
upload_2022-1-9_18-45-53.png


Since its a single line, pretty much, what I'm suggesting is
a) confirm its short to ground.
b) then narrow down location by disconnecting at the far end and working back toward the fuse.

This is assuming its doesn't become obvious just by looking..
 
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According to the diagram at coordinates B-34, page 8-162, cavity 3 does feed the blower switch so that is a possibility, then X12-14R feeds radio, and branches to B1-18W feeds back up light circuit, then branches to D1-18BK which ends at TS flasher

Looks to me like the text fuse chart is AFU
 
I think it is AFU because my brake lamps are working fine, obviously not part of this circuit.

With the blown fuse I have no turn signals, no reverse lights and no heater blower. Everything else seems to be working fine, including brake lamps, marker lamps, hazards and horn.

The radio was disconnected a long time ago at the connector. I have an aftermarket stereo that has its own circuit.

I took a look at the wires at the flasher terminal and they looked ok. Nothing was exposed from the sux inches of wire between the terminal and the harness.

I took a look at the fuse box and everything looked ok underneath. No rust or corrosion. The clips look fine, nothing loose and no melting.

Sometime this week I will disconnect the rear harness and neutral safety switch and do some continuity checks and report back.

thanks so far.
 
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Flashers are garbage today, chased my tail a few times, short version, replaced both flashers with the NAPA solid state flasher.

It's pricey, about $15, but have them in all old Mopars, no more issues, directionals flash with authority, like a new car.
 
hotrod swinger said:
Yes I have a multimeter with a resistance setting.
Click to expand...
OK Great.
"a) confirm its short to ground. "
Remove the flasher fuse.
One probe touching the fuse clip which connects to the circuit wire.
Touch the other probe to ground.

If there is anything other than MegaOhms or infinate resistance reading, then there is a short to ground in that circuit.
 
Another thing you might consider is one type of short finder kit. This is a low rated breaker and resistor that you clip into the fuse which is blowing. Because of the short it will sit there and cycle. Meanwhile, the high current in the shorted wire generates a magnetic field. The tool comes with a deal that resembles an ammeter which is a fairly sensitive meter, that when held near a shorted wire, will indicate. You can move it along the harness to localize the short

KD Tools 2524 Short Circuit Detector | electric stud finder store

Yet another way is to "rig" an old socket with an 1157 and clip the 1157 bulb directly across the fuse clips. Now, the lamp will light and also protect the circuit. You can wiggle wires, etc, and look for changes in the bulb
 
Mattax said:
One probe touching the fuse clip which connects to the circuit wire.
Click to expand...
If its not obvious which side is the feed buss and which clip is the circuit,
the circuit clip is probably the one furthest away from the cable entry.
Here's one that was for sale that supposed to be from a '73 Valiant

Connector side
upload_2022-1-9_20-36-55.png


Fuse side
upload_2022-1-9_20-39-53.png
 
Mattax said:
One probe touching the fuse clip which connects to the circuit wire.
Touch the other probe to ground.
Click to expand...

My measurement with the multimeter is 0.03. I measured from where the last arrow is pointing to ground.
 
hotrod swinger said:
My measurement with the multimeter is 0.03.
Click to expand...
0.03 Ohms? That's pretty much zero. Most meters struggle with any low ohm measurements. Put the leads together and and might show the same. Doesnt really matter for what your doing but something to be aware of. For a comparison, my multimeter showed 0.6 ohms and 2.2 ohms for the readings across an 1157 bulb.

WHen you have time, start disconnecting and see if you can narrow down what component or section of wire is grounding.
If the ground is eliminated by disconnecting something, then check the something.
Earlier, I suggested starting at the flasher unit. I still think thats fine.
Keep in mind that if its a bare wire, then moving wires around may temporarily break the contact with the sheet metal.
That may have been what happened before.
 
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This DVM shows open clearly
upload_2022-1-9_21-10-44.png


Here's continuity with the aligators clipped together. Sometimes it will hit zero, sometimes not. Depends on how good the contact is throughout.
upload_2022-1-9_21-13-4.png


Since this is an autoranging meter, I have to be careful to look at the top. If its showing K then I need to multiply the number on the screen by 1000 to get ohms.
 
Actually it was 0.3 not 0.03 and same reading when I touch the leads. I’ll take both to be essentially 0.

FYI my two signal flashers measure 32 and 58 ohms.

Measurements at fuse box:

Disconnect flasher: reading is 0
Disconnect turn signal switch connector: reading is 0
Disconnect rear harness: reading is 0
Disconnect heater blower switch: reading is 0
Disconnect NSS/reverse lamp engine bay connector: reading is “1 .”
 
FYI, earlier this year I was battling a small parasitic draw. That draw was eliminated by disconnecting the NSS/reverse lamp engine bay connector. At the time I pulled my gauge cluster to discover a number of wires that had melted together, including the main red and black wires. I thought I had carefully repaired all of these wires, and I haven’t had a problem since then.

Is there anything else I can check now before resorting to pulling the cluster? Where else can I check?
 
Keep in mind it can be a short hidden in the harness. If for example you short something to ground and heat up the wiring the insulation can melt and cause "cross connect" to other wires in the harness.

Sometimes you need to take "extreme" measures. If you are certain that you have it down to the daisy chaing wire that feeds off the fuse to various loads, pick one "in the middle" and cut the wire far enough from the connector that you can splice it, or pull the terminal out of the connector and cut it there to solder back later. If the short is in the now isolated section from that point to the end of the "daisy chain" at least you have cut it down some.

Also bear in mind "pinched wires." I know you isolated the rear harness but a good example is the rear harness where it goes under the rear seat and into the trunk. That is an easy place to be pinched.
 
hotrod swinger said:
FYI, earlier this year I was battling a small parasitic draw. That draw was eliminated by disconnecting the NSS/reverse lamp engine bay connector. At the time I pulled my gauge cluster to discover a number of wires that had melted together, including the main red and black wires. I thought I had carefully repaired all of these wires, and I haven’t had a problem since then.

Is there anything else I can check now before resorting to pulling the cluster? Where else can I check?
Click to expand...
I would certainly re-visit the "melted" area, untape some of it and examine
 
hotrod swinger said:
Disconnect NSS/reverse lamp engine bay connector: reading is “1 .”
Click to expand...
You mean 1 Ohm?

If so, then one of the wires or conenctors is touching ground.
upload_2022-1-9_22-42-24.png


With the flasher unit removed, connector CE14 is a break in the circuit.
That leaves everything highlighted.
How about the wire in the engine compartment between the bulkhead connector and connector CE40 ?

It could be cross wire short, but there aren't that many wires that connect direct to ground.

I don't know what the wire harness looks like on your car.
The next suggestion might narrow it down, but it may not save you from taking down the harness and unwrapping a section or more.

Since you're not using the radio connector. Take the terminals out of CE 13 and cut there. That will isolate C1 and X12 from B1 and D1. Then see which two are still in touch with ground. Later you can install a new terminal to reconnect, or make a splice. You may have to add a bit of wire so the wires aren't tugging on the repaired junction. I've found some of the underdash wiring doesn't have much allowance for strain relief and the last thing you need is an electrical wire under tension.
 
hotrod swinger said:
It looks good but how do I test it?
Click to expand...
How is that wire different than the rest of the circuit?
Not sure what you're asking.
You've proven that something conductive after the fuse is touching ground. So now look for bare wires or connectors that could be touching body or the engine/trans. Any place that wire is pinched, rubbing, hanging, or melted is what I'd be looking for.
The segment in the engine bay could be laying on the exhaust manifold or rubbing on something, that's what I was thinking. The book shows CE40 may also have other wires in it, one back to the reverse lights and another optional one.
See what matches on your car to what is in the book.
You can always isolate that section by disconnecting at the bulkhead. Its just not the easiest connector to remove. Take your time.
 
I removed the bulkhead connector that contains the reverse lights and that eliminates the ground. Does that mean the problem is between that connector and the transmission?

I should say with that connector removed I have no turn signals or blower.

That bulkhead connector has the wiper harness, the two reverse light wires and a third wire. What is the third wire?
 
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